switch_jitterbuffer.c

Go to the documentation of this file.

/*
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005-2014, Anthony Minessale II <anthm@freeswitch.org>
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 *
 * The Initial Developer of the Original Code is
 * Anthony Minessale II <anthm@freeswitch.org>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Anthony Minessale II <anthm@freeswitch.org>
 * Dragos Oancea <dragos@freeswitch.org>
 *
 * switch_jitterbuffer.c -- Audio/Video Jitter Buffer
 *
 */
#include <switch.h>
#include <switch_jitterbuffer.h>
#include "private/switch_hashtable_private.h"

#define NACK_TIME 80000
#define RENACK_TIME 100000
#define MAX_FRAME_PADDING 2
#define MAX_MISSING_SEQ 20
#define jb_debug(_jb, _level, _format, ...) if (_jb->debug_level >= _level) switch_log_printf(SWITCH_CHANNEL_SESSION_LOG_CLEAN(_jb->session), SWITCH_LOG_ALERT, "JB:%p:%s:%d/%d lv:%d ln:%.4d sz:%.3u/%.3u/%.3u/%.3u c:%.3u %.3u/%.3u/%.3u/%.3u %.2f%% ->" _format, (void *) _jb, (jb->type == SJB_TEXT ? "txt" : (jb->type == SJB_AUDIO ? "aud" : "vid")), _jb->allocated_nodes, _jb->visible_nodes, _level, __LINE__,  _jb->min_frame_len, _jb->max_frame_len, _jb->frame_len, _jb->complete_frames, _jb->period_count, _jb->consec_good_count, _jb->period_good_count, _jb->consec_miss_count, _jb->period_miss_count, _jb->period_miss_pct, __VA_ARGS__)

//const char *TOKEN_1 = "ONE";
//const char *TOKEN_2 = "TWO";

struct switch_jb_s;

static inline int check_jb_size(switch_jb_t *jb);

typedef struct switch_jb_node_s {
        struct switch_jb_s *parent;
        switch_rtp_packet_t packet;
        uint32_t len;
        uint8_t visible;
        uint8_t bad_hits;
        struct switch_jb_node_s *prev;
        struct switch_jb_node_s *next;
        /* used for counting the number of partial or complete frames currently in the JB */
        switch_bool_t complete_frame_mark;
} switch_jb_node_t;

typedef struct switch_jb_stats_s {
        uint32_t reset_too_big;
        uint32_t reset_missing_frames;
        uint32_t reset_ts_jump;
        uint32_t reset_error;
        uint32_t reset;
        uint32_t size_max;
        uint32_t size_est;
        uint32_t acceleration;
        uint32_t expand;
        uint32_t jitter_max_ms;
        int estimate_ms;
        int buffer_size_ms;
} switch_jb_stats_t;

typedef struct switch_jb_jitter_s {
        double *estimate;
        uint32_t samples_per_second;
        uint32_t samples_per_frame;
        uint32_t drop_gap;
        switch_jb_stats_t stats;
} switch_jb_jitter_t;

struct switch_jb_s {
        struct switch_jb_node_s *node_list;
        uint32_t last_target_seq;
        uint32_t highest_read_ts;
        uint32_t highest_dropped_ts;
        uint32_t highest_read_seq;
        uint32_t highest_wrote_ts;
        uint16_t highest_wrote_seq;
        uint16_t target_seq;
        uint32_t target_ts;
        uint32_t last_target_ts;
        uint16_t psuedo_seq;
        uint16_t last_psuedo_seq;
        uint32_t visible_nodes;
        uint32_t allocated_nodes;
        uint32_t complete_frames;
        uint32_t frame_len;
        uint32_t min_frame_len;
        uint32_t max_frame_len;
        uint32_t highest_frame_len;
        uint32_t period_miss_count;
        uint32_t consec_miss_count;
        uint32_t period_miss_inc;
        double period_miss_pct;
        uint32_t period_good_count;
        uint32_t consec_good_count;
        uint32_t period_count;
        uint32_t dropped;
        uint32_t samples_per_frame;
        uint32_t samples_per_second;
        uint32_t bitrate_control;
        uint32_t video_low_bitrate;
        uint8_t write_init;
        uint8_t read_init;
        uint8_t debug_level;
        uint16_t next_seq;
        switch_size_t last_len;
        switch_inthash_t *missing_seq_hash;
        switch_inthash_t *node_hash;
        switch_inthash_t *node_hash_ts;
        switch_mutex_t *mutex;
        switch_mutex_t *list_mutex;
        switch_memory_pool_t *pool;
        int free_pool;
        int drop_flag;
        switch_jb_flag_t flags;
        switch_jb_type_t type;
        switch_core_session_t *session;
        switch_jb_jitter_t jitter;
        switch_channel_t *channel;
        uint32_t buffer_lag;
        uint32_t flush;
        uint32_t packet_count;
        uint32_t max_packet_len;
        uint32_t period_len;
        uint32_t nack_saved_the_day;
        uint32_t nack_didnt_save_the_day;
        switch_bool_t elastic;
        switch_codec_t *codec;
};


static int node_cmp(const void *l, const void *r)
{
        switch_jb_node_t *a = (switch_jb_node_t *) l;
        switch_jb_node_t *b = (switch_jb_node_t *) r;

        if (!a->visible) return 0;
        if (!b->visible) return 1;

        return ntohs(a->packet.header.seq) - ntohs(b->packet.header.seq);
}

//http://www.chiark.greenend.org.uk/~sgtatham/algorithms/listsort.c
switch_jb_node_t *sort_nodes(switch_jb_node_t *list, int (*cmp)(const void *, const void *)) {
        switch_jb_node_t *p, *q, *e, *tail;
        int insize, nmerges, psize, qsize, i;

        if (!list) {
                return NULL;
        }

        insize = 1;

        while (1) {
                p = list;
                list = NULL;
                tail = NULL;

                nmerges = 0;  /* count number of merges we do in this pass */

                while (p) {
                        nmerges++;  /* there exists a merge to be done */
                                    /* step `insize' places along from p */
                        q = p;
                        psize = 0;
                        for (i = 0; i < insize; i++) {
                                psize++;
                                q = q->next;
                                if (!q) break;
                        }

                        /* if q hasn't fallen off end, we have two lists to merge */
                        qsize = insize;

                        /* now we have two lists; merge them */
                        while (psize > 0 || (qsize > 0 && q)) {

                                /* decide whether next switch_jb_node_t of merge comes from p or q */
                                if (psize == 0) {
                                        /* p is empty; e must come from q. */
                                        e = q; q = q->next; qsize--;
                                } else if (qsize == 0 || !q) {
                                        /* q is empty; e must come from p. */
                                        e = p; p = p->next; psize--;
                                } else if (cmp(p,q) <= 0) {
                                        /* First switch_jb_node_t of p is lower (or same);
                                         * e must come from p. */
                                        e = p; p = p->next; psize--;
                                } else {
                                        /* First switch_jb_node_t of q is lower; e must come from q. */
                                        e = q; q = q->next; qsize--;
                                }

                                /* add the next switch_jb_node_t to the merged list */
                                if (tail) {
                                        tail->next = e;
                                } else {
                                        list = e;
                                }

                                /* Maintain reverse pointers in a doubly linked list. */
                                e->prev = tail;

                                tail = e;
                        }

                        /* now p has stepped `insize' places along, and q has too */
                        p = q;
                }

                tail->next = NULL;

                /* If we have done only one merge, we're finished. */
                if (nmerges <= 1)   /* allow for nmerges==0, the empty list case */
                        return list;

                /* Otherwise repeat, merging lists twice the size */
                insize *= 2;
        }
}

// static inline void thin_frames(switch_jb_t *jb, int freq, int max);


static inline switch_jb_node_t *new_node(switch_jb_t *jb)
{
        switch_jb_node_t *np;

        switch_mutex_lock(jb->list_mutex);

        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) {
                        break;
                }
        }

        if (!np) {
                int mult = 2;

                if (jb->type != SJB_VIDEO) {
                        mult = 2;
                } else {
                        if (jb->max_packet_len > mult) {
                                mult = jb->max_packet_len;
                        }
                }

                if (jb->allocated_nodes > jb->max_frame_len * mult) {
                        jb_debug(jb, 2, "ALLOCATED FRAMES TOO HIGH! %d\n", jb->allocated_nodes);
                        jb->jitter.stats.reset_too_big++;
                        switch_jb_reset(jb);
                        switch_mutex_unlock(jb->list_mutex);
                        return NULL;
                }
                
                np = switch_core_alloc(jb->pool, sizeof(*np));
                jb->allocated_nodes++;
                np->next = jb->node_list;
                if (np->next) {
                        np->next->prev = np;
                }
                jb->node_list = np;

        }

        switch_assert(np);
        np->bad_hits = 0;
        np->visible = 1;
        jb->visible_nodes++;
        np->parent = jb;

        switch_mutex_unlock(jb->list_mutex);

        return np;
}

static inline void push_to_top(switch_jb_t *jb, switch_jb_node_t *node)
{
        if (node == jb->node_list) {
                jb->node_list = node->next;
        } else if (node->prev) {
                node->prev->next = node->next;
        }

        if (node->next) {
                node->next->prev = node->prev;
        }

        node->next = jb->node_list;
        node->prev = NULL;

        if (node->next) {
                node->next->prev = node;
        }

        jb->node_list = node;

        switch_assert(node->next != node);
        switch_assert(node->prev != node);
}

static inline void hide_node(switch_jb_node_t *node, switch_bool_t pop)
{
        switch_jb_t *jb = node->parent;

        switch_mutex_lock(jb->list_mutex);

        if (node->visible) {
                node->visible = 0;
                node->bad_hits = 0;
                jb->visible_nodes--;

                if (pop) {
                        push_to_top(jb, node);
                }
        }

        if (jb->node_hash_ts) {
                switch_core_inthash_delete(jb->node_hash_ts, node->packet.header.ts);
        }

        if (switch_core_inthash_delete(jb->node_hash, node->packet.header.seq)) {
                if (node->complete_frame_mark && jb->type == SJB_VIDEO) {
                        jb->complete_frames--;
                        node->complete_frame_mark = FALSE;
                }
        }

        switch_mutex_unlock(jb->list_mutex);
}

static inline void sort_free_nodes(switch_jb_t *jb)
{
        switch_mutex_lock(jb->list_mutex);
        jb->node_list = sort_nodes(jb->node_list, node_cmp);
        switch_mutex_unlock(jb->list_mutex);
}

static inline void hide_nodes(switch_jb_t *jb)
{
        switch_jb_node_t *np;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                hide_node(np, SWITCH_FALSE);
        }
        switch_mutex_unlock(jb->list_mutex);
}

static inline switch_bool_t packet_vad(switch_jb_t *jb, switch_rtp_packet_t *packet, switch_size_t len) {
        void *payload = packet ? (packet->ebody ? packet->ebody : packet->body) : NULL;
        uint16_t payload_len = len;

        if (payload && payload_len > 0) {
                switch_bool_t ret = SWITCH_FALSE, *ret_p = &ret;
                switch_codec_control_type_t ret_t;

                switch_core_media_codec_control(jb->session, SWITCH_MEDIA_TYPE_AUDIO,
                                                SWITCH_IO_WRITE, SCC_AUDIO_VAD,
                                                SCCT_STRING, (void *)payload,
                                                SCCT_INT, (void *)&payload_len,
                                                &ret_t, (void *)&ret_p);

                return ret;
        }

        return SWITCH_TRUE;
}

static inline void drop_ts(switch_jb_t *jb, uint32_t ts)
{
        switch_jb_node_t *np;
        int x = 0;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) continue;

                if (ts == np->packet.header.ts) {
                        hide_node(np, SWITCH_FALSE);
                        x++;
                }
        }

        if (x) {
                sort_free_nodes(jb);
        }

        switch_mutex_unlock(jb->list_mutex);
}

static inline switch_jb_node_t *jb_find_lowest_seq(switch_jb_t *jb, uint32_t ts)
{
        switch_jb_node_t *np, *lowest = NULL;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) continue;

                if (ts && ts != np->packet.header.ts) continue;

                if (!lowest || ntohs(lowest->packet.header.seq) > ntohs(np->packet.header.seq)) {
                        lowest = np;
                }
        }
        switch_mutex_unlock(jb->list_mutex);

        return lowest;
}

static inline switch_jb_node_t *jb_find_lowest_node(switch_jb_t *jb)
{
        switch_jb_node_t *np, *lowest = NULL;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) continue;

                if (!lowest || ntohl(lowest->packet.header.ts) > ntohl(np->packet.header.ts)) {
                        lowest = np;
                }
        }
        switch_mutex_unlock(jb->list_mutex);

        return lowest ? lowest : NULL;
}

static inline uint32_t jb_find_lowest_ts(switch_jb_t *jb)
{
        switch_jb_node_t *lowest = jb_find_lowest_node(jb);

        return lowest ? lowest->packet.header.ts : 0;
}

#if 0
static inline void thin_frames(switch_jb_t *jb, int freq, int max)
{
        switch_jb_node_t *node, *this_node;
        int i = -1;
        int dropped = 0;

        switch_mutex_lock(jb->list_mutex);
        node = jb->node_list;

        while (node && dropped <= max) {
                this_node = node;
                node = node->next;
                
                if (this_node->visible) {
                        i++;
                } else {
                        continue;
                }

                if ((i % freq) == 0) {
                        drop_ts(jb, this_node->packet.header.ts);
                        dropped++;
                }
        }

        sort_free_nodes(jb);
        switch_mutex_unlock(jb->list_mutex);
}

static inline switch_jb_node_t *jb_find_highest_node(switch_jb_t *jb)
{
        switch_jb_node_t *np, *highest = NULL;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) continue;

                if (!highest || ntohl(highest->packet.header.ts) < ntohl(np->packet.header.ts)) {
                        highest = np;
                }
        }
        switch_mutex_unlock(jb->list_mutex);

        return highest ? highest : NULL;
}


static inline uint32_t jb_find_highest_ts(switch_jb_t *jb)
{
        switch_jb_node_t *highest = jb_find_highest_node(jb);

        return highest ? highest->packet.header.ts : 0;
}

static inline void drop_newest_frame(switch_jb_t *jb)
{
        uint32_t ts = jb_find_highest_ts(jb);

        drop_ts(jb, ts);
        jb_debug(jb, 1, "Dropping highest frame ts:%u\n", ntohl(ts));
}




static inline switch_jb_node_t *jb_find_penultimate_node(switch_jb_t *jb)
{
        switch_jb_node_t *np, *highest = NULL, *second_highest = NULL;

        switch_mutex_lock(jb->list_mutex);
        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) continue;

                if (!highest || ntohl(highest->packet.header.ts) < ntohl(np->packet.header.ts)) {
                        if (highest) second_highest = highest;
                        highest = np;
                }
        }
        switch_mutex_unlock(jb->list_mutex);

        return second_highest ? second_highest : highest;
}
#endif

static inline void jb_hit(switch_jb_t *jb)
{
        jb->period_good_count++;
        jb->consec_good_count++;
        jb->consec_miss_count = 0;
}

static void jb_frame_inc_line(switch_jb_t *jb, int i, int line)
{
        uint32_t old_frame_len = jb->frame_len;

        if (i == 0) {
                jb->frame_len = jb->min_frame_len;
                goto end;
        }

        if (i > 0) {
                if ((jb->frame_len + i) < jb->max_frame_len) {
                        jb->frame_len += i;
                } else {
                        jb->frame_len = jb->max_frame_len;
                }

                goto end;
        }

        /* i < 0 */
        if ((jb->frame_len + i) > jb->min_frame_len) {
                jb->frame_len += i;
        } else {
                jb->frame_len = jb->min_frame_len;
        }

 end:

        if (jb->frame_len > jb->highest_frame_len) {
                jb->highest_frame_len = jb->frame_len;
        }

        if (old_frame_len != jb->frame_len) {
                jb_debug(jb, 1, "%d Change framelen from %u to %u\n", line, old_frame_len, jb->frame_len);

                //if (jb->session) {
                //      switch_core_session_request_video_refresh(jb->session);
                //}
        }

}

#define jb_frame_inc(_jb, _i) jb_frame_inc_line(_jb, _i, __LINE__)


static inline void jb_miss(switch_jb_t *jb)
{
        jb->period_miss_count++;
        jb->consec_miss_count++;
        jb->consec_good_count = 0;
}

#if 0
static inline int verify_oldest_frame(switch_jb_t *jb)
{
        switch_jb_node_t *lowest = NULL, *np = NULL;
        int r = 0;

        lowest = jb_find_lowest_node(jb);

        if (!lowest || !(lowest = jb_find_lowest_seq(jb, lowest->packet.header.ts))) {
                goto end;
        }

        switch_mutex_lock(jb->mutex);

        jb->node_list = sort_nodes(jb->node_list, node_cmp);

        for (np = lowest->next; np; np = np->next) {

                if (!np->visible) continue;

                if (ntohs(np->packet.header.seq) != ntohs(np->prev->packet.header.seq) + 1) {
                        uint32_t val = (uint32_t)htons(ntohs(np->prev->packet.header.seq) + 1);

                        if (!switch_core_inthash_find(jb->missing_seq_hash, val)) {
                                switch_core_inthash_insert(jb->missing_seq_hash, val, (void *)(intptr_t)1);
                        }
                        break;
                }

                if (np->packet.header.ts != lowest->packet.header.ts || !np->next) {
                        r = 1;
                }
        }

        switch_mutex_unlock(jb->mutex);

 end:

        return r;
}
#endif

static inline void drop_oldest_frame(switch_jb_t *jb)
{
        uint32_t ts = jb_find_lowest_ts(jb);

        drop_ts(jb, ts);
        jb_debug(jb, 1, "Dropping oldest frame ts:%u\n", ntohl(ts));
}



#if 0
static inline void drop_second_newest_frame(switch_jb_t *jb)
{
        switch_jb_node_t *second_newest = jb_find_penultimate_node(jb);

        if (second_newest) {
                drop_ts(jb, second_newest->packet.header.ts);
                jb_debug(jb, 1, "Dropping second highest frame ts:%u\n", ntohl(second_newest->packet.header.ts));
        }
}
#endif

static inline int check_seq(uint16_t a, uint16_t b)
{
        a = ntohs(a);
        b = ntohs(b);

        if (a >= b || (b > a && b > USHRT_MAX / 2 && a < USHRT_MAX / 2)) {
                return 1;
        }

        return 0;
}

static inline int check_ts(uint32_t a, uint32_t b)
{
        a = ntohl(a);
        b = ntohl(b);

        if (a > b || (b > a && b > UINT_MAX / 2 && a < UINT_MAX / 2)) {
                return 1;
        }

        return 0;
}

static inline void add_node(switch_jb_t *jb, switch_rtp_packet_t *packet, switch_size_t len)
{
        switch_jb_node_t *node = new_node(jb);

        if (!node) {
                return;
        }


        node->packet = *packet;
        node->len = len;

        switch_core_inthash_insert(jb->node_hash, node->packet.header.seq, node);

        if (jb->node_hash_ts) {
                switch_core_inthash_insert(jb->node_hash_ts, node->packet.header.ts, node);
        }

        jb_debug(jb, (packet->header.m ? 2 : 3), "PUT packet last_ts:%u ts:%u seq:%u%s\n",
                         ntohl(jb->highest_wrote_ts), ntohl(node->packet.header.ts), ntohs(node->packet.header.seq), packet->header.m ? " <MARK>" : "");

        if (jb->write_init && jb->type == SJB_VIDEO) {
                int seq_diff = 0, ts_diff = 0;

                if (ntohs(jb->highest_wrote_seq) > (USHRT_MAX - 100) && ntohs(packet->header.seq) < 100) {
                        seq_diff = (USHRT_MAX - ntohs(jb->highest_wrote_seq)) + ntohs(packet->header.seq);
                } else {
                        seq_diff = abs(((int)ntohs(packet->header.seq) - ntohs(jb->highest_wrote_seq)));
                }

                if (ntohl(jb->highest_wrote_ts) > (UINT_MAX - 1000) && ntohl(node->packet.header.ts) < 1000) {
                        ts_diff = (UINT_MAX - ntohl(node->packet.header.ts)) + ntohl(node->packet.header.ts);
                } else {
                        ts_diff = abs((int)((int64_t)ntohl(node->packet.header.ts) - (int64_t)ntohl(jb->highest_wrote_ts)));
                }

                if (((seq_diff >= 100) || (ts_diff > (900000 * 5)))) {
                        jb_debug(jb, 2, "CHANGE DETECTED, PUNT %u\n", abs(((int)ntohs(packet->header.seq) - ntohs(jb->highest_wrote_seq))));
                        jb->jitter.stats.reset_ts_jump++;
                        switch_jb_reset(jb);
                }
        }

        if (!jb->write_init || ntohs(packet->header.seq) > ntohs(jb->highest_wrote_seq) ||
                (ntohs(jb->highest_wrote_seq) > USHRT_MAX - 100 && ntohs(packet->header.seq) < 100) ) {
                jb->highest_wrote_seq = packet->header.seq;
        }

        if (jb->type == SJB_VIDEO) {
                jb->packet_count++;
                
                if (jb->write_init && check_seq(packet->header.seq, jb->highest_wrote_seq) && check_ts(node->packet.header.ts, jb->highest_wrote_ts)) {
                        jb_debug(jb, 2, "WRITE frame ts: %u complete=%u/%u n:%u\n", ntohl(node->packet.header.ts), jb->complete_frames , jb->frame_len, jb->visible_nodes);
                        jb->highest_wrote_ts = packet->header.ts;
                        jb->complete_frames++;

                        jb->packet_count--;
                        if (jb->packet_count > jb->max_packet_len) {
                                jb->max_packet_len = jb->packet_count;
                        }
                        jb->packet_count = 1;
                        node->complete_frame_mark = TRUE;
                } else if (!jb->write_init) {
                        jb->highest_wrote_ts = packet->header.ts;
                }
        } else {
                if (jb->write_init || jb->type == SJB_TEXT || jb->type == SJB_AUDIO) {
                        jb_debug(jb, 2, "WRITE frame ts: %u complete=%u/%u n:%u\n", ntohl(node->packet.header.ts), jb->complete_frames , jb->frame_len, jb->visible_nodes);
                        jb->complete_frames++;
                } else {
                        jb->highest_wrote_ts = packet->header.ts;
                }
        }

        if (!jb->write_init) jb->write_init = 1;
}

static inline void increment_ts(switch_jb_t *jb)
{
        if (!jb->target_ts) return;

        jb->last_psuedo_seq = jb->psuedo_seq;
        jb->last_target_ts = jb->target_ts;
        jb->target_ts = htonl((ntohl(jb->target_ts) + jb->samples_per_frame));
        jb->psuedo_seq++;
}

static inline void set_read_ts(switch_jb_t *jb, uint32_t ts)
{
        if (!ts) return;

        jb->last_psuedo_seq = jb->psuedo_seq;
        jb->last_target_ts = ts;
        jb->target_ts = htonl((ntohl(jb->last_target_ts) + jb->samples_per_frame));
        jb->psuedo_seq++;
}


static inline void increment_seq(switch_jb_t *jb)
{
        jb->last_target_seq = jb->target_seq;
        jb->target_seq = htons((ntohs(jb->target_seq) + 1));
}

static inline void decrement_seq(switch_jb_t *jb)
{
        jb->last_target_seq = jb->target_seq;
        jb->target_seq = htons((ntohs(jb->target_seq) - 1));
}

static inline void set_read_seq(switch_jb_t *jb, uint16_t seq)
{
        jb->last_target_seq = seq;
        jb->target_seq = htons((ntohs(jb->last_target_seq) + 1));
}

static inline switch_status_t jb_next_packet_by_seq(switch_jb_t *jb, switch_jb_node_t **nodep)
{
        switch_jb_node_t *node = NULL;

 top:

        if (jb->type == SJB_VIDEO) {
                if (jb->dropped) {
                        jb->dropped = 0;
                        jb_debug(jb, 2, "%s", "DROPPED FRAME DETECTED RESYNCING\n");
                        jb->target_seq = 0;

                        if (jb->session) {
                                switch_core_session_request_video_refresh(jb->session);
                        }
                }
        }

        if (!jb->target_seq) {
                if ((node = switch_core_inthash_find(jb->node_hash, jb->target_seq))) {
                        jb_debug(jb, 2, "FOUND rollover seq: %u\n", ntohs(jb->target_seq));
                } else if ((node = jb_find_lowest_seq(jb, 0))) {
                        jb_debug(jb, 2, "No target seq using seq: %u as a starting point\n", ntohs(node->packet.header.seq));
                } else {
                        jb_debug(jb, 1, "%s", "No nodes available....\n");
                }
                jb_hit(jb);
        } else if ((node = switch_core_inthash_find(jb->node_hash, jb->target_seq))) {
                jb_debug(jb, 2, "FOUND desired seq: %u\n", ntohs(jb->target_seq));
                jb_hit(jb);
        } else {
                jb_debug(jb, 2, "MISSING desired seq: %u\n", ntohs(jb->target_seq));
                jb_miss(jb);

                if (jb->type == SJB_VIDEO) {
                        int x;

                        if (jb->session) {
                                switch_core_session_request_video_refresh(jb->session);
                        }

                        for (x = 0; x < 10; x++) {
                                increment_seq(jb);
                                if ((node = switch_core_inthash_find(jb->node_hash, jb->target_seq))) {
                                        jb_debug(jb, 2, "FOUND incremental seq: %u\n", ntohs(jb->target_seq));

                                        if (node->packet.header.m ||  node->packet.header.ts == jb->highest_read_ts) {
                                                jb_debug(jb, 2, "%s", "SAME FRAME DROPPING\n");
                                                jb->dropped++;
                                                drop_ts(jb, node->packet.header.ts);
                                                jb->highest_dropped_ts = ntohl(node->packet.header.ts);


                                                if (jb->period_miss_count > 2 && jb->period_miss_inc < 1) {
                                                        jb->period_miss_inc++;
                                                        jb_frame_inc(jb, 1);
                                                }

                                                node = NULL;
                                                goto top;
                                        }
                                        break;
                                } else {
                                        jb_debug(jb, 2, "MISSING incremental seq: %u\n", ntohs(jb->target_seq));
                                }
                        }
                        
                } else {
                        increment_seq(jb);
                }
        }

        *nodep = node;

        if (node) {
                set_read_seq(jb, node->packet.header.seq);
                return SWITCH_STATUS_SUCCESS;
        }

        return SWITCH_STATUS_NOTFOUND;

}


static inline switch_status_t jb_next_packet_by_ts(switch_jb_t *jb, switch_jb_node_t **nodep)
{
        switch_jb_node_t *node = NULL;

        if (!jb->target_ts) {
                if ((node = jb_find_lowest_node(jb))) {
                        jb_debug(jb, 2, "No target ts using ts: %u as a starting point\n", ntohl(node->packet.header.ts));
                } else {
                        jb_debug(jb, 1, "%s", "No nodes available....\n");
                }
                jb_hit(jb);
        } else if ((node = switch_core_inthash_find(jb->node_hash_ts, jb->target_ts))) {
                jb_debug(jb, 2, "FOUND desired ts: %u\n", ntohl(jb->target_ts));
                jb_hit(jb);
        } else {
                jb_debug(jb, 2, "MISSING desired ts: %u\n", ntohl(jb->target_ts));
                jb_miss(jb);
                increment_ts(jb);
        }

        *nodep = node;

        if (node) {
                set_read_ts(jb, node->packet.header.ts);
                node->packet.header.seq = htons(jb->psuedo_seq);
                return SWITCH_STATUS_SUCCESS;
        }

        return SWITCH_STATUS_NOTFOUND;

}

static inline int check_jb_size(switch_jb_t *jb)
{
        switch_jb_node_t *np;
        uint16_t seq_hs, target_seq_hs;
        uint16_t l_seq = 0;
        uint16_t h_seq = 0;
        uint16_t count = 0;
        uint16_t old = 0;

        switch_mutex_lock(jb->list_mutex);

        target_seq_hs = ntohs(jb->target_seq);

        for (np = jb->node_list; np; np = np->next) {
                if (!np->visible) {
                        continue;
                }

                seq_hs = ntohs(np->packet.header.seq);
                if (target_seq_hs > seq_hs) {
                        hide_node(np, SWITCH_FALSE);
                        old++;
                        continue;
                }

                if (count == 0) {
                        l_seq = h_seq = seq_hs;
                }

                count++;

                if (seq_hs < l_seq) {
                        l_seq = seq_hs;
                }

                if (seq_hs > h_seq) {
                        h_seq = seq_hs;
                }
        }

        if (count > jb->jitter.stats.size_max) {
                jb->jitter.stats.size_max = count;
        }

        if (jb->jitter.stats.size_est == 0) {
                jb->jitter.stats.size_est = count;
        } else {
                jb->jitter.stats.size_est = ((99 * jb->jitter.stats.size_est) + (1 * count)) / 100;
        }

        /* update the stats every x packets */
        if (target_seq_hs % 50 == 0) {
                int packet_ms = jb->jitter.samples_per_frame / (jb->jitter.samples_per_second / 1000);

                jb->jitter.stats.estimate_ms = (*jb->jitter.estimate) / jb->jitter.samples_per_second * 1000;
                if (jb->channel) {
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_size_max_ms", "%u", jb->jitter.stats.size_max * packet_ms);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_size_est_ms", "%u", jb->jitter.stats.size_est * packet_ms);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_acceleration_ms", "%u", jb->jitter.stats.acceleration * packet_ms);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_expand_ms", "%u", jb->jitter.stats.expand * packet_ms);
                }

                if (jb->jitter.stats.jitter_max_ms < jb->jitter.stats.estimate_ms) {
                        jb->jitter.stats.jitter_max_ms = jb->jitter.stats.estimate_ms;
                }

                if (jb->channel) {
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_jitter_max_ms", "%u", jb->jitter.stats.jitter_max_ms);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_jitter_est_ms", "%u", jb->jitter.stats.estimate_ms);
                }
        }

        if (old) {
                sort_free_nodes(jb);
        }

        switch_mutex_unlock(jb->list_mutex);

        jb_debug(jb, SWITCH_LOG_INFO, "JITTER buffersize %u == %u old[%u] target[%u] seq[%u|%u]\n", count, h_seq - l_seq + 1, old, target_seq_hs, l_seq, h_seq);

        return count;
}

static inline switch_status_t jb_next_packet_by_seq_with_acceleration(switch_jb_t *jb, switch_jb_node_t **nodep)
{
        switch_status_t status = jb_next_packet_by_seq(jb, nodep);
        switch_rtp_packet_t *packet;
        uint32_t len;
        uint16_t seq = ntohs(jb->target_seq);

        /* When using a Codec that provides voice activity detection ex. Opus, use it to
           select packet to drop/accelerate. */

        if (jb->elastic && jb->jitter.estimate && (jb->visible_nodes * jb->jitter.samples_per_frame) > 0 && jb->jitter.samples_per_second) {
                int visible_not_old = check_jb_size(jb);

                jb->jitter.stats.estimate_ms = (int)((*jb->jitter.estimate) / ((jb->jitter.samples_per_second)) * 1000);
                jb->jitter.stats.buffer_size_ms = (int)((visible_not_old * jb->jitter.samples_per_frame) / (jb->jitter.samples_per_second / 1000));

                /* We try to accelerate in order to remove delay when the jitter buffer is 3x larger than the estimation. */
                if (jb->jitter.stats.buffer_size_ms > (3 * jb->jitter.stats.estimate_ms) && jb->jitter.stats.buffer_size_ms > 60) {
                        if (status == SWITCH_STATUS_SUCCESS) {
                                packet = &(*nodep)->packet;
                                seq = ntohs((*nodep)->packet.header.seq);
                                len = (*nodep)->len;
                        }

                        if (jb->jitter.drop_gap > 0) {
                                jb_debug(jb, SWITCH_LOG_INFO, "JITTER estimation %dms buffersize %d/%d %dms seq:%u [drop-gap][%d]\n",
                                                 jb->jitter.stats.estimate_ms, jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms, seq, jb->jitter.drop_gap);
                                jb->jitter.drop_gap--;
                        } else {
                                if (status != SWITCH_STATUS_SUCCESS || packet_vad(jb, packet, len) == SWITCH_FALSE) {
                                        jb->jitter.drop_gap = 3;
                                        if (status != SWITCH_STATUS_SUCCESS) {
                                                jb_debug(jb, SWITCH_LOG_INFO, "JITTER estimation n/a buffersize %d/%d %dms seq:%u [drop-missing/no-plc]\n",
                                                                 jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms, seq);
                                        } else {
                                                jb_debug(jb, SWITCH_LOG_INFO, "JITTER estimation %dms buffersize %d/%d %dms seq:%u ACCELERATE [drop]\n",
                                                                 jb->jitter.stats.estimate_ms, jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms, seq);
                                        }

                                        jb->jitter.stats.acceleration++;

                                        return jb_next_packet_by_seq(jb, nodep);
                                } else {
                                        jb_debug(jb, SWITCH_LOG_INFO, "JITTER estimation %dms buffersize %d/%d %dms seq:%u [drop-skip-vad]\n",
                                                         jb->jitter.stats.estimate_ms, jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms, seq);
                                }
                        }
                } else {
                        jb_debug(jb, 2, "JITTER estimation %dms buffersize %d/%d %dms\n",
                                         jb->jitter.stats.estimate_ms, jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms);
                }
        }

        return status;
}

static inline switch_status_t jb_next_packet(switch_jb_t *jb, switch_jb_node_t **nodep)
{
        if (jb->samples_per_frame) {
                return jb_next_packet_by_ts(jb, nodep);
        }

        if (jb->elastic && jb->jitter.estimate) {
                return jb_next_packet_by_seq_with_acceleration(jb, nodep);
        }

        return jb_next_packet_by_seq(jb, nodep);
}

static inline void free_nodes(switch_jb_t *jb)
{
        switch_mutex_lock(jb->list_mutex);
        jb->node_list = NULL;
        switch_mutex_unlock(jb->list_mutex);
}

SWITCH_DECLARE(void) switch_jb_ts_mode(switch_jb_t *jb, uint32_t samples_per_frame, uint32_t samples_per_second)
{
        jb->samples_per_frame = samples_per_frame;
        jb->samples_per_second = samples_per_second;
        switch_core_inthash_init(&jb->node_hash_ts);
}

SWITCH_DECLARE(void) switch_jb_set_jitter_estimator(switch_jb_t *jb, double *jitter, uint32_t samples_per_frame, uint32_t samples_per_second)
{
        if (jb && jitter) {
                memset(&jb->jitter, 0, sizeof(switch_jb_jitter_t));
                if (jb->channel) {
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_max_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_size_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_acceleration_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_expand_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_jitter_max_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_jitter_ms", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_count", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_too_big", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_missing_frames", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_ts_jump", "%u", 0);
                        switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_error", "%u", 0);
                }

                jb->jitter.estimate = jitter;
                jb->jitter.samples_per_frame = samples_per_frame;
                jb->jitter.samples_per_second = samples_per_second;
                jb->jitter.drop_gap = 5;
        }
}

SWITCH_DECLARE(void) switch_jb_set_session(switch_jb_t *jb, switch_core_session_t *session)
{
        const char *var;

        if (session) {
                jb->codec = switch_core_session_get_read_codec(session);
                jb->session = session;
                jb->channel = switch_core_session_get_channel(session);
                if (jb->type == SJB_AUDIO) {
                        if (!strcmp(jb->codec->implementation->iananame, "opus")) {
                                if (switch_channel_var_true(jb->channel, "rtp_jitter_buffer_accelerate")) {
                                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "audio codec is %s, accelerate on\n", jb->codec->implementation->iananame);
                                        jb->elastic = SWITCH_TRUE;
                                } else {
                                        switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG1, "audio codec is %s, accelerate off\n", jb->codec->implementation->iananame);
                                        jb->elastic = SWITCH_FALSE;
                                }
                        } else {
                                switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG1, "audio codec is not Opus: %s\n", jb->codec->implementation->iananame);
                                jb->elastic = SWITCH_FALSE;
                        }
                }

                if (jb->type == SJB_VIDEO && !switch_test_flag(jb, SJB_QUEUE_ONLY) &&
                        (var = switch_channel_get_variable_dup(jb->channel, "jb_video_low_bitrate", SWITCH_FALSE, -1))) {
                        int tmp = atoi(var);

                        if (tmp >= 128 && tmp <= 10240) {
                                jb->video_low_bitrate = (uint32_t)tmp;
                        }
                }
        }
}

SWITCH_DECLARE(void) switch_jb_set_flag(switch_jb_t *jb, switch_jb_flag_t flag)
{
        switch_set_flag(jb, flag);
}

SWITCH_DECLARE(void) switch_jb_clear_flag(switch_jb_t *jb, switch_jb_flag_t flag)
{
        switch_clear_flag(jb, flag);
}

SWITCH_DECLARE(int) switch_jb_poll(switch_jb_t *jb)
{
        if (jb->type == SJB_TEXT) {
                if (jb->complete_frames < jb->frame_len) {
                        if (jb->complete_frames && !jb->buffer_lag) {
                                jb->buffer_lag = 10;
                        }
                        if (jb->buffer_lag && --jb->buffer_lag == 0) {
                                jb->flush = 1;
                        }
                }
        }

        return (jb->complete_frames >= jb->frame_len) || jb->flush;
}

SWITCH_DECLARE(int) switch_jb_frame_count(switch_jb_t *jb)
{
        return jb->complete_frames;
}

SWITCH_DECLARE(void) switch_jb_debug_level(switch_jb_t *jb, uint8_t level)
{
        jb->debug_level = level;
}

SWITCH_DECLARE(void) switch_jb_reset(switch_jb_t *jb)
{
        jb->jitter.stats.reset++;
        if (jb->channel) {
                switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_count", "%u", jb->jitter.stats.reset);
                switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_too_big", "%u", jb->jitter.stats.reset_too_big);
                switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_missing_frames", "%u", jb->jitter.stats.reset_missing_frames);
                switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_ts_jump", "%u", jb->jitter.stats.reset_ts_jump);
                switch_channel_set_variable_printf(jb->channel, "rtp_jb_reset_error", "%u", jb->jitter.stats.reset_error);
        }

        if (jb->type == SJB_VIDEO) {
                switch_mutex_lock(jb->mutex);
                switch_core_inthash_destroy(&jb->missing_seq_hash);
                switch_core_inthash_init(&jb->missing_seq_hash);
                switch_mutex_unlock(jb->mutex);

                if (jb->session) {
                        switch_core_session_request_video_refresh(jb->session);
                }
        }

        jb_debug(jb, 2, "%s", "RESET BUFFER\n");

        switch_mutex_lock(jb->mutex);
        hide_nodes(jb);
        switch_mutex_unlock(jb->mutex);

        jb->drop_flag = 0;
        jb->last_target_seq = 0;
        jb->target_seq = 0;
        jb->write_init = 0;
        jb->highest_wrote_seq = 0;
        jb->highest_wrote_ts = 0;
        jb->next_seq = 0;
        jb->highest_read_ts = 0;
        jb->highest_read_seq = 0;
        jb->read_init = 0;
        jb->complete_frames = 0;
        jb->period_miss_count = 0;
        jb->consec_miss_count = 0;
        jb->period_miss_pct = 0;
        jb->period_good_count = 0;
        jb->consec_good_count = 0;
        jb->period_count = 0;
        jb->period_miss_inc = 0;
        jb->target_ts = 0;
        jb->last_target_ts = 0;
}

SWITCH_DECLARE(uint32_t) switch_jb_get_nack_success(switch_jb_t *jb) 
{
        uint32_t nack_recovered; /*count*/
        switch_mutex_lock(jb->mutex);
        nack_recovered = jb->nack_saved_the_day + jb->nack_didnt_save_the_day;
        switch_mutex_unlock(jb->mutex);
        return nack_recovered;
}

SWITCH_DECLARE(uint32_t) switch_jb_get_packets_per_frame(switch_jb_t *jb) 
{
        uint32_t ppf;
        switch_mutex_lock(jb->mutex);
        ppf = jb->packet_count; /* get current packets per frame */
        switch_mutex_unlock(jb->mutex);
        return ppf;
}

SWITCH_DECLARE(switch_status_t) switch_jb_peek_frame(switch_jb_t *jb, uint32_t ts, uint16_t seq, int peek, switch_frame_t *frame)
{
        switch_jb_node_t *node = NULL;
        if (seq) {
                uint16_t want_seq = seq + peek;
                node = switch_core_inthash_find(jb->node_hash, htons(want_seq));
        } else if (ts && jb->samples_per_frame) {
                uint32_t want_ts = ts + (peek * jb->samples_per_frame);
                node = switch_core_inthash_find(jb->node_hash_ts, htonl(want_ts));
        }

        if (node) {
                frame->seq = ntohs(node->packet.header.seq);
                frame->timestamp = ntohl(node->packet.header.ts);
                frame->m = node->packet.header.m;
                frame->datalen = node->len - SWITCH_RTP_HEADER_LEN;

                if (frame->data && frame->buflen > node->len - SWITCH_RTP_HEADER_LEN) {
                        memcpy(frame->data, node->packet.body, node->len - SWITCH_RTP_HEADER_LEN);
                }
                return SWITCH_STATUS_SUCCESS;
        }

        return SWITCH_STATUS_FALSE;
}

SWITCH_DECLARE(switch_status_t) switch_jb_get_frames(switch_jb_t *jb, uint32_t *min_frame_len, uint32_t *max_frame_len, uint32_t *cur_frame_len, uint32_t *highest_frame_len)
{

        switch_mutex_lock(jb->mutex);

        if (min_frame_len) {
                *min_frame_len = jb->min_frame_len;
        }

        if (max_frame_len) {
                *max_frame_len = jb->max_frame_len;
        }

        if (cur_frame_len) {
                *cur_frame_len = jb->frame_len;
        }

        switch_mutex_unlock(jb->mutex);

        return SWITCH_STATUS_SUCCESS;
}

SWITCH_DECLARE(switch_status_t) switch_jb_set_frames(switch_jb_t *jb, uint32_t min_frame_len, uint32_t max_frame_len)
{
        int lowest = 0;

        switch_mutex_lock(jb->mutex);

        if (jb->frame_len == jb->min_frame_len) lowest = 1;

        jb->min_frame_len = min_frame_len;
        jb->max_frame_len = max_frame_len;

        if (jb->frame_len > jb->max_frame_len) {
                jb->frame_len = jb->max_frame_len;
        }

        if (jb->frame_len < jb->min_frame_len) {
                jb->frame_len = jb->min_frame_len;
        }

        if (jb->frame_len > jb->highest_frame_len) {
                jb->highest_frame_len = jb->frame_len;
        }

        if (lowest) {
                jb->frame_len = jb->min_frame_len;
        }

        switch_mutex_unlock(jb->mutex);

        return SWITCH_STATUS_SUCCESS;
}

SWITCH_DECLARE(switch_status_t) switch_jb_create(switch_jb_t **jbp, switch_jb_type_t type,
                                                                                                 uint32_t min_frame_len, uint32_t max_frame_len, switch_memory_pool_t *pool)
{
        switch_jb_t *jb;
        int free_pool = 0;

        if (!pool) {
                switch_core_new_memory_pool(&pool);
                free_pool = 1;
        }

        jb = switch_core_alloc(pool, sizeof(*jb));
        jb->free_pool = free_pool;
        jb->min_frame_len = jb->frame_len = min_frame_len;
        jb->max_frame_len = max_frame_len;
        jb->pool = pool;
        jb->type = type;
        jb->highest_frame_len = jb->frame_len;

        if (jb->type == SJB_VIDEO) {
                switch_core_inthash_init(&jb->missing_seq_hash);
                jb->period_len = 2500;
        } else {
                jb->period_len = 250;
        }
        
        switch_core_inthash_init(&jb->node_hash);
        switch_mutex_init(&jb->mutex, SWITCH_MUTEX_NESTED, pool);
        switch_mutex_init(&jb->list_mutex, SWITCH_MUTEX_NESTED, pool);

        *jbp = jb;

        return SWITCH_STATUS_SUCCESS;
}

SWITCH_DECLARE(switch_status_t) switch_jb_destroy(switch_jb_t **jbp)
{
        switch_jb_t *jb = *jbp;
        *jbp = NULL;

        if (jb->type == SJB_VIDEO && !switch_test_flag(jb, SJB_QUEUE_ONLY)) {
                jb_debug(jb, 3, "Stats: NACK saved the day: %u\n", jb->nack_saved_the_day);
                jb_debug(jb, 3, "Stats: NACK was late: %u\n", jb->nack_didnt_save_the_day);
                jb_debug(jb, 3, "Stats: Hash entrycount: missing_seq_hash %u\n", switch_hashtable_count(jb->missing_seq_hash));
        }
        if (jb->type == SJB_VIDEO) {
                switch_core_inthash_destroy(&jb->missing_seq_hash);
        }
        switch_core_inthash_destroy(&jb->node_hash);

        if (jb->node_hash_ts) {
                switch_core_inthash_destroy(&jb->node_hash_ts);
        }

        free_nodes(jb);

        if (jb->free_pool) {
                switch_core_destroy_memory_pool(&jb->pool);
        }

        return SWITCH_STATUS_SUCCESS;
}

SWITCH_DECLARE(uint32_t) switch_jb_pop_nack(switch_jb_t *jb)
{
        switch_hash_index_t *hi = NULL;
        uint32_t nack = 0;
        uint16_t blp = 0;
        uint16_t least = 0;
        int i = 0;
        void *val;
        const void *var;

        if (jb->type != SJB_VIDEO) {
                return 0;
        }

        switch_mutex_lock(jb->mutex);

 top:

        for (hi = switch_core_hash_first_iter(jb->missing_seq_hash, hi); hi; hi = switch_core_hash_next(&hi)) {
                uint16_t seq;
                //const char *token;
                switch_time_t then = 0;

                switch_core_hash_this(hi, &var, NULL, &val);
                //token = (const char *) val;

                //if (token == TOKEN_2) {
                        //switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "SKIP %u %s\n", ntohs(*((uint16_t *) var)), token);
                        //printf("WTf\n");
                //      continue;
                //}

                seq = ntohs(*((uint16_t *) var));
                then = (intptr_t) val;

                if (then != 1 && ((uint32_t)(switch_time_now() - then)) < RENACK_TIME) {
                        jb_debug(jb, 3, "NACKABLE seq %u too soon to repeat\n", seq);
                        continue;
                }

                //if (then != 1) {
                //      jb_debug(jb, 3, "NACKABLE seq %u not too soon to repeat %lu\n", seq, switch_time_now() - then);
                //}

                if (seq < ntohs(jb->target_seq) - jb->frame_len) {
                        jb_debug(jb, 3, "NACKABLE seq %u expired\n", seq);
                        switch_core_inthash_delete(jb->missing_seq_hash, (uint32_t)htons(seq));
                        goto top;
                }

                if (!least || seq < least) {
                        least = seq;
                }
        }

        switch_safe_free(hi);

        if (least && switch_core_inthash_delete(jb->missing_seq_hash, (uint32_t)htons(least))) {
                jb_debug(jb, 3, "Found NACKABLE seq %u\n", least);
                nack = (uint32_t) htons(least);
                switch_core_inthash_insert(jb->missing_seq_hash, nack, (void *) (intptr_t)switch_time_now());

                for(i = 0; i < 16; i++) {
                        if (switch_core_inthash_delete(jb->missing_seq_hash, (uint32_t)htons(least + i + 1))) {
                                switch_core_inthash_insert(jb->missing_seq_hash, (uint32_t)htons(least + i + 1), (void *)(intptr_t)switch_time_now());
                                jb_debug(jb, 3, "Found addtl NACKABLE seq %u\n", least + i + 1);
                                blp |= (1 << i);
                        }
                }

                blp = htons(blp);
                nack |= (uint32_t) blp << 16;

                //jb_frame_inc(jb, 1);
        }

        switch_mutex_unlock(jb->mutex);


        return nack;
}

SWITCH_DECLARE(switch_status_t) switch_jb_put_packet(switch_jb_t *jb, switch_rtp_packet_t *packet, switch_size_t len)
{
        uint32_t i;
        uint16_t want = ntohs(jb->next_seq), got = ntohs(packet->header.seq);

        if (len >= SWITCH_RTP_MAX_PACKET_LEN) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "trying to put %" SWITCH_SIZE_T_FMT " bytes exceeding buffer, truncate to %" SWITCH_SIZE_T_FMT "\n", len, SWITCH_RTP_MAX_PACKET_LEN);
                len = SWITCH_RTP_MAX_PACKET_LEN;
        }

        switch_mutex_lock(jb->mutex);

        if (jb->highest_dropped_ts) {
                if (ntohl(packet->header.ts) < jb->highest_dropped_ts) {
                        jb_debug(jb, 2, "%s", "TS ALREADY DROPPED, DROPPING PACKET\n");
                        switch_mutex_unlock(jb->mutex);
                        return SWITCH_STATUS_SUCCESS;
                }
                jb->highest_dropped_ts = 0;
        }


        if (!want) want = got;

        if (switch_test_flag(jb, SJB_QUEUE_ONLY) || jb->type == SJB_AUDIO || jb->type == SJB_TEXT) {
                jb->next_seq = htons(got + 1);
        } else {

                if (switch_core_inthash_delete(jb->missing_seq_hash, (uint32_t)htons(got))) {
                        if (got < ntohs(jb->target_seq)) {
                                jb_debug(jb, 2, "got nacked seq %u too late\n", got);
                                jb_frame_inc(jb, 1);
                                jb->nack_didnt_save_the_day++;
                        } else {
                                jb_debug(jb, 2, "got nacked %u saved the day!\n", got);
                                jb->nack_saved_the_day++;
                        }
                }

                if (got > want) {
                        if (got - want > jb->max_frame_len && got - want > 17) {
                                jb_debug(jb, 2, "Missing %u frames, Resetting\n", got - want);
                                jb->jitter.stats.reset_missing_frames++;
                                switch_jb_reset(jb);
                        } else {
                                if (jb->type != SJB_VIDEO && jb->frame_len < got - want) {
                                        jb_frame_inc(jb, 1);
                                }

                                jb_debug(jb, 2, "GOT %u WANTED %u; MARK SEQS MISSING %u - %u\n", got, want, want, got - 1);

                                for (i = want; i < got; i++) {
                                        jb_debug(jb, 2, "MARK MISSING %u ts:%u\n", i, ntohl(packet->header.ts));
                                        switch_core_inthash_insert(jb->missing_seq_hash, (uint32_t)htons(i), (void *)(intptr_t)1);
                                }
                        }
                }

                if (got >= want || (want - got) > 1000) {
                        jb->next_seq = htons(got + 1);
                }
        }

        add_node(jb, packet, len);

        if (switch_test_flag(jb, SJB_QUEUE_ONLY) && jb->max_packet_len && jb->max_frame_len * 2 > jb->max_packet_len &&
                        jb->allocated_nodes > jb->max_frame_len * 2 - 1) {
                while ((jb->max_frame_len * 2 - jb->visible_nodes) < jb->max_packet_len) {
                        drop_oldest_frame(jb);
                }
        } else if (switch_test_flag(jb, SJB_QUEUE_ONLY) && jb->max_packet_len && jb->max_frame_len * 2 < jb->max_packet_len) {
                /* rtp_nack_buffer_size less than initial max_packet_len */
                drop_oldest_frame(jb);
        }

        switch_mutex_unlock(jb->mutex);

        return SWITCH_STATUS_SUCCESS;
}

SWITCH_DECLARE(switch_status_t) switch_jb_get_packet_by_seq(switch_jb_t *jb, uint16_t seq, switch_rtp_packet_t *packet, switch_size_t *len)
{
        switch_jb_node_t *node;
        switch_status_t status = SWITCH_STATUS_NOTFOUND;

        switch_mutex_lock(jb->mutex);
        if ((node = switch_core_inthash_find(jb->node_hash, seq))) {
                jb_debug(jb, 2, "Found buffered seq: %u\n", ntohs(seq));
                *packet = node->packet;
                *len = node->len;
                packet->header.version = 2;
                status = SWITCH_STATUS_SUCCESS;
        } else {
                jb_debug(jb, 2, "Missing buffered seq: %u\n", ntohs(seq));
        }
        switch_mutex_unlock(jb->mutex);

        return status;
}

SWITCH_DECLARE(switch_size_t) switch_jb_get_last_read_len(switch_jb_t *jb)
{
        return jb->last_len;
}

SWITCH_DECLARE(switch_status_t) switch_jb_get_packet(switch_jb_t *jb, switch_rtp_packet_t *packet, switch_size_t *len)
{
        switch_jb_node_t *node = NULL;
        switch_status_t status;
        int plc = 0;
        
        switch_mutex_lock(jb->mutex);

        if (jb->complete_frames == 0) {
                jb->flush = 0;
                switch_goto_status(SWITCH_STATUS_BREAK, end);
        }

        if (jb->complete_frames < jb->frame_len) {

                switch_jb_poll(jb);

                if (!jb->flush) {
                        jb_debug(jb, 2, "BUFFERING %u/%u\n", jb->complete_frames , jb->frame_len);
                        switch_goto_status(SWITCH_STATUS_MORE_DATA, end);
                }
        }

        jb_debug(jb, 2, "GET PACKET %u/%u n:%d\n", jb->complete_frames , jb->frame_len, jb->visible_nodes);

        if (++jb->period_count >= jb->period_len) {

                if (jb->consec_good_count >= (jb->period_len - 5)) {
                        jb_frame_inc(jb, -1);
                }

                jb->period_count = 1;
                jb->period_miss_inc = 0;
                jb->period_miss_count = 0;
                jb->period_good_count = 0;
                jb->consec_miss_count = 0;
                jb->consec_good_count = 0;

                if (jb->type == SJB_VIDEO && jb->channel && jb->video_low_bitrate) {
                        //switch_time_t now = switch_time_now();
                        //int ok = (now - jb->last_bitrate_change) > 10000;

                        if (switch_channel_test_flag(jb->channel, CF_VIDEO_BITRATE_UNMANAGABLE) && jb->frame_len == jb->min_frame_len) {
                                jb_debug(jb, 2, "%s", "Allow BITRATE changes\n");
                                switch_channel_clear_flag_recursive(jb->channel, CF_VIDEO_BITRATE_UNMANAGABLE);
                                jb->bitrate_control = 0;
                                if (jb->session) {
                                        switch_core_session_request_video_refresh(jb->session);
                                }
                        } else if (!switch_channel_test_flag(jb->channel, CF_VIDEO_BITRATE_UNMANAGABLE) && jb->frame_len > jb->max_frame_len / 2) {
                                switch_core_session_message_t msg = { 0 };

                                jb->bitrate_control = jb->video_low_bitrate;
                                
                                msg.message_id = SWITCH_MESSAGE_INDICATE_BITRATE_REQ;
                                msg.numeric_arg = jb->bitrate_control * 1024;
                                msg.from = __FILE__;

                                jb_debug(jb, 2, "Force BITRATE to %d\n", jb->bitrate_control);

                                switch_core_session_receive_message(jb->session, &msg);
                                switch_channel_set_flag_recursive(jb->channel, CF_VIDEO_BITRATE_UNMANAGABLE);
                                if (jb->session) {
                                        switch_core_session_request_video_refresh(jb->session);
                                }
                        }
                }
        }


        jb->period_miss_pct = ((double)jb->period_miss_count / jb->period_count) * 100;

        //if (jb->period_miss_pct > 60.0f) {
        //      jb_debug(jb, 2, "Miss percent %02f too high, resetting buffer.\n", jb->period_miss_pct);
        //      switch_jb_reset(jb);
        //}

        if ((status = jb_next_packet(jb, &node)) == SWITCH_STATUS_SUCCESS) {
                jb_debug(jb, 2, "Found next frame cur ts: %u seq: %u\n", htonl(node->packet.header.ts), htons(node->packet.header.seq));

                if (!jb->read_init || check_seq(node->packet.header.seq, jb->highest_read_seq)) {
                        jb->highest_read_seq = node->packet.header.seq;
                }

                if (jb->type != SJB_VIDEO ||
                        (jb->read_init && check_seq(node->packet.header.seq, jb->highest_read_seq) && check_ts(node->packet.header.ts, jb->highest_read_ts))) {

                        if (jb->type != SJB_VIDEO) {
                                jb->complete_frames--;
                        }
                        jb_debug(jb, 2, "READ frame ts: %u complete=%u/%u n:%u\n", ntohl(node->packet.header.ts), jb->complete_frames , jb->frame_len, jb->visible_nodes);
                        jb->highest_read_ts = node->packet.header.ts;
                } else if (!jb->read_init) {
                        jb->highest_read_ts = node->packet.header.ts;
                }

                if (!jb->read_init) jb->read_init = 1;
        } else {
                if (jb->type == SJB_VIDEO) {
                        //switch_jb_reset(jb);

                        switch(status) {
                        case SWITCH_STATUS_RESTART:
                                jb_debug(jb, 2, "%s", "Error encountered ask for new keyframe\n");
                                switch_goto_status(SWITCH_STATUS_RESTART, end);
                        case SWITCH_STATUS_NOTFOUND:
                        default:
                                jb_debug(jb, 2, "%s", "No frames found wait for more\n");
                                switch_goto_status(SWITCH_STATUS_MORE_DATA, end);
                        }
                } else {
                        switch(status) {
                        case SWITCH_STATUS_RESTART:
                                jb_debug(jb, 2, "%s", "Error encountered\n");
                                jb->jitter.stats.reset_error++;
                                switch_jb_reset(jb);
                                switch_goto_status(SWITCH_STATUS_RESTART, end);
                        case SWITCH_STATUS_NOTFOUND:
                        default:
                                if (jb->consec_miss_count > jb->frame_len) {
                                        //switch_jb_reset(jb);
                                        jb_frame_inc(jb, 1);
                                        jb_debug(jb, 2, "%s", "Too many frames not found, RESIZE\n");
                                        switch_goto_status(SWITCH_STATUS_RESTART, end);
                                } else {
                                        if (jb->elastic) {
                                                int visible_not_old = check_jb_size(jb);

                                                jb->jitter.stats.estimate_ms = (int)((*jb->jitter.estimate) / ((jb->jitter.samples_per_second)) * 1000);
                                                jb->jitter.stats.buffer_size_ms = (int)((visible_not_old * jb->jitter.samples_per_frame) / (jb->jitter.samples_per_second / 1000));
                                                /* When playing PLC, we take the oportunity to expand the buffer if the jitter buffer is smaller than the 3x the estimated jitter. */
                                                if (jb->jitter.stats.buffer_size_ms < (3 * jb->jitter.stats.estimate_ms)) {
                                                        jb_debug(jb, SWITCH_LOG_INFO, "JITTER estimation %dms buffersize %d/%d %dms EXPAND [plc]\n",
                                                                         jb->jitter.stats.estimate_ms, jb->complete_frames, jb->frame_len, jb->jitter.stats.buffer_size_ms);
                                                        jb->jitter.stats.expand++;
                                                        decrement_seq(jb);
                                                } else {
                                                        jb_debug(jb, 2, "%s", "Frame not found suggest PLC\n");
                                                }
                                        } else {
                                                jb_debug(jb, 2, "%s", "Frame not found suggest PLC\n");
                                        }

                                        plc = 1;
                                        switch_goto_status(SWITCH_STATUS_NOTFOUND, end);
                                }
                        }
                }
        }

        *packet = node->packet;
        *len = node->len;
        jb->last_len = *len;
        packet->header.version = 2;
        hide_node(node, SWITCH_TRUE);

        jb_debug(jb, 2, "GET packet ts:%u seq:%u %s\n", ntohl(packet->header.ts), ntohs(packet->header.seq), packet->header.m ? " <MARK>" : "");

 end:

        if (plc) {
                uint16_t seq;
                uint32_t ts = 0;

                if (jb->samples_per_frame) {
                        seq = htons(jb->last_psuedo_seq);
                        ts = jb->last_target_ts;
                } else {
                        seq = jb->last_target_seq;
                }

                packet->header.seq = seq;
                packet->header.ts = ts;
        }

        switch_mutex_unlock(jb->mutex);
        
        if (jb->type == SJB_VIDEO) {
                if (jb->complete_frames > jb->max_frame_len * 2) {
                        jb_debug(jb, 2, "JB TOO BIG (%d), RESET\n", jb->complete_frames);
                        switch_jb_reset(jb);
                }
        } else {
                int too_big = (int)(jb->max_frame_len * 1.5);
                if (jb->visible_nodes > too_big && status == SWITCH_STATUS_SUCCESS) {
                        status = SWITCH_STATUS_TIMEOUT;
                }
        }
        
        return status;
}

/* For Emacs:
 * Local Variables:
 * mode:c
 * indent-tabs-mode:t
 * tab-width:4
 * c-basic-offset:4
 * End:
 * For VIM:
 * vim:set softtabstop=4 shiftwidth=4 tabstop=4 noet:
 */