pthread_frame.c 29 KB
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/*
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * Frame multithreading support functions
 * @see doc/multithreading.txt
 */

#include "config.h"

#include <stdint.h>

#if HAVE_PTHREADS
#include <pthread.h>
#elif HAVE_W32THREADS
#include "compat/w32pthreads.h"
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#elif HAVE_OS2THREADS
#include "compat/os2threads.h"
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#endif

#include "avcodec.h"
#include "internal.h"
#include "pthread_internal.h"
#include "thread.h"

#include "libavutil/avassert.h"
#include "libavutil/buffer.h"
#include "libavutil/common.h"
#include "libavutil/cpu.h"
#include "libavutil/frame.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"

/**
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 * Context used by codec threads and stored in their AVCodecInternal thread_ctx.
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 */
typedef struct PerThreadContext {
    struct FrameThreadContext *parent;

    pthread_t      thread;
    int            thread_init;
    pthread_cond_t input_cond;      ///< Used to wait for a new packet from the main thread.
    pthread_cond_t progress_cond;   ///< Used by child threads to wait for progress to change.
    pthread_cond_t output_cond;     ///< Used by the main thread to wait for frames to finish.

    pthread_mutex_t mutex;          ///< Mutex used to protect the contents of the PerThreadContext.
    pthread_mutex_t progress_mutex; ///< Mutex used to protect frame progress values and progress_cond.

    AVCodecContext *avctx;          ///< Context used to decode packets passed to this thread.

    AVPacket       avpkt;           ///< Input packet (for decoding) or output (for encoding).
    uint8_t       *buf;             ///< backup storage for packet data when the input packet is not refcounted
    int            allocated_buf_size; ///< Size allocated for buf

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    AVFrame *frame;                 ///< Output frame (for decoding) or input (for encoding).
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    int     got_frame;              ///< The output of got_picture_ptr from the last avcodec_decode_video() call.
    int     result;                 ///< The result of the last codec decode/encode() call.

    enum {
        STATE_INPUT_READY,          ///< Set when the thread is awaiting a packet.
        STATE_SETTING_UP,           ///< Set before the codec has called ff_thread_finish_setup().
        STATE_GET_BUFFER,           /**<
                                     * Set when the codec calls get_buffer().
                                     * State is returned to STATE_SETTING_UP afterwards.
                                     */
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        STATE_GET_FORMAT,           /**<
                                     * Set when the codec calls get_format().
                                     * State is returned to STATE_SETTING_UP afterwards.
                                     */
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        STATE_SETUP_FINISHED        ///< Set after the codec has called ff_thread_finish_setup().
    } state;

    /**
     * Array of frames passed to ff_thread_release_buffer().
     * Frames are released after all threads referencing them are finished.
     */
    AVFrame *released_buffers;
    int  num_released_buffers;
    int      released_buffers_allocated;

    AVFrame *requested_frame;       ///< AVFrame the codec passed to get_buffer()
    int      requested_flags;       ///< flags passed to get_buffer() for requested_frame
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    const enum AVPixelFormat *available_formats; ///< Format array for get_format()
    enum AVPixelFormat result_format;            ///< get_format() result
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} PerThreadContext;

/**
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 * Context stored in the client AVCodecInternal thread_ctx.
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 */
typedef struct FrameThreadContext {
    PerThreadContext *threads;     ///< The contexts for each thread.
    PerThreadContext *prev_thread; ///< The last thread submit_packet() was called on.

    pthread_mutex_t buffer_mutex;  ///< Mutex used to protect get/release_buffer().

    int next_decoding;             ///< The next context to submit a packet to.
    int next_finished;             ///< The next context to return output from.

    int delaying;                  /**<
                                    * Set for the first N packets, where N is the number of threads.
                                    * While it is set, ff_thread_en/decode_frame won't return any results.
                                    */

    int die;                       ///< Set when threads should exit.
} FrameThreadContext;

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#define THREAD_SAFE_CALLBACKS(avctx) \
((avctx)->thread_safe_callbacks || (!(avctx)->get_buffer && (avctx)->get_buffer2 == avcodec_default_get_buffer2))

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/**
 * Codec worker thread.
 *
 * Automatically calls ff_thread_finish_setup() if the codec does
 * not provide an update_thread_context method, or if the codec returns
 * before calling it.
 */
static attribute_align_arg void *frame_worker_thread(void *arg)
{
    PerThreadContext *p = arg;
    FrameThreadContext *fctx = p->parent;
    AVCodecContext *avctx = p->avctx;
    const AVCodec *codec = avctx->codec;

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    pthread_mutex_lock(&p->mutex);
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    while (1) {
            while (p->state == STATE_INPUT_READY && !fctx->die)
                pthread_cond_wait(&p->input_cond, &p->mutex);

        if (fctx->die) break;

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        if (!codec->update_thread_context && THREAD_SAFE_CALLBACKS(avctx))
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            ff_thread_finish_setup(avctx);

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        av_frame_unref(p->frame);
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        p->got_frame = 0;
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        p->result = codec->decode(avctx, p->frame, &p->got_frame, &p->avpkt);
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        if ((p->result < 0 || !p->got_frame) && p->frame->buf[0]) {
            if (avctx->internal->allocate_progress)
                av_log(avctx, AV_LOG_ERROR, "A frame threaded decoder did not "
                       "free the frame on failure. This is a bug, please report it.\n");
            av_frame_unref(p->frame);
        }

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        if (p->state == STATE_SETTING_UP) ff_thread_finish_setup(avctx);

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        pthread_mutex_lock(&p->progress_mutex);
#if 0 //BUFREF-FIXME
        for (i = 0; i < MAX_BUFFERS; i++)
            if (p->progress_used[i] && (p->got_frame || p->result<0 || avctx->codec_id != AV_CODEC_ID_H264)) {
                p->progress[i][0] = INT_MAX;
                p->progress[i][1] = INT_MAX;
            }
#endif
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        p->state = STATE_INPUT_READY;

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        pthread_cond_broadcast(&p->progress_cond);
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        pthread_cond_signal(&p->output_cond);
        pthread_mutex_unlock(&p->progress_mutex);
    }
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    pthread_mutex_unlock(&p->mutex);
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    return NULL;
}

/**
 * Update the next thread's AVCodecContext with values from the reference thread's context.
 *
 * @param dst The destination context.
 * @param src The source context.
 * @param for_user 0 if the destination is a codec thread, 1 if the destination is the user's thread
 */
static int update_context_from_thread(AVCodecContext *dst, AVCodecContext *src, int for_user)
{
    int err = 0;

    if (dst != src) {
        dst->time_base = src->time_base;
        dst->width     = src->width;
        dst->height    = src->height;
        dst->pix_fmt   = src->pix_fmt;

        dst->coded_width  = src->coded_width;
        dst->coded_height = src->coded_height;

        dst->has_b_frames = src->has_b_frames;
        dst->idct_algo    = src->idct_algo;

        dst->bits_per_coded_sample = src->bits_per_coded_sample;
        dst->sample_aspect_ratio   = src->sample_aspect_ratio;
        dst->dtg_active_format     = src->dtg_active_format;

        dst->profile = src->profile;
        dst->level   = src->level;

        dst->bits_per_raw_sample = src->bits_per_raw_sample;
        dst->ticks_per_frame     = src->ticks_per_frame;
        dst->color_primaries     = src->color_primaries;

        dst->color_trc   = src->color_trc;
        dst->colorspace  = src->colorspace;
        dst->color_range = src->color_range;
        dst->chroma_sample_location = src->chroma_sample_location;

        dst->hwaccel = src->hwaccel;
        dst->hwaccel_context = src->hwaccel_context;
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        dst->channels       = src->channels;
        dst->sample_rate    = src->sample_rate;
        dst->sample_fmt     = src->sample_fmt;
        dst->channel_layout = src->channel_layout;
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    }

    if (for_user) {
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        dst->delay       = src->thread_count - 1;
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        dst->coded_frame = src->coded_frame;
    } else {
        if (dst->codec->update_thread_context)
            err = dst->codec->update_thread_context(dst, src);
    }

    return err;
}

/**
 * Update the next thread's AVCodecContext with values set by the user.
 *
 * @param dst The destination context.
 * @param src The source context.
 * @return 0 on success, negative error code on failure
 */
static int update_context_from_user(AVCodecContext *dst, AVCodecContext *src)
{
#define copy_fields(s, e) memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);
    dst->flags          = src->flags;

    dst->draw_horiz_band= src->draw_horiz_band;
    dst->get_buffer2    = src->get_buffer2;
#if FF_API_GET_BUFFER
FF_DISABLE_DEPRECATION_WARNINGS
    dst->get_buffer     = src->get_buffer;
    dst->release_buffer = src->release_buffer;
FF_ENABLE_DEPRECATION_WARNINGS
#endif

    dst->opaque   = src->opaque;
    dst->debug    = src->debug;
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    dst->debug_mv = src->debug_mv;
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    dst->slice_flags = src->slice_flags;
    dst->flags2      = src->flags2;

    copy_fields(skip_loop_filter, subtitle_header);

    dst->frame_number     = src->frame_number;
    dst->reordered_opaque = src->reordered_opaque;
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    dst->thread_safe_callbacks = src->thread_safe_callbacks;
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    if (src->slice_count && src->slice_offset) {
        if (dst->slice_count < src->slice_count) {
            int *tmp = av_realloc(dst->slice_offset, src->slice_count *
                                  sizeof(*dst->slice_offset));
            if (!tmp) {
                av_free(dst->slice_offset);
                return AVERROR(ENOMEM);
            }
            dst->slice_offset = tmp;
        }
        memcpy(dst->slice_offset, src->slice_offset,
               src->slice_count * sizeof(*dst->slice_offset));
    }
    dst->slice_count = src->slice_count;
    return 0;
#undef copy_fields
}

/// Releases the buffers that this decoding thread was the last user of.
static void release_delayed_buffers(PerThreadContext *p)
{
    FrameThreadContext *fctx = p->parent;

    while (p->num_released_buffers > 0) {
        AVFrame *f;

        pthread_mutex_lock(&fctx->buffer_mutex);

        // fix extended data in case the caller screwed it up
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        av_assert0(p->avctx->codec_type == AVMEDIA_TYPE_VIDEO ||
                   p->avctx->codec_type == AVMEDIA_TYPE_AUDIO);
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        f = &p->released_buffers[--p->num_released_buffers];
        f->extended_data = f->data;
        av_frame_unref(f);

        pthread_mutex_unlock(&fctx->buffer_mutex);
    }
}

static int submit_packet(PerThreadContext *p, AVPacket *avpkt)
{
    FrameThreadContext *fctx = p->parent;
    PerThreadContext *prev_thread = fctx->prev_thread;
    const AVCodec *codec = p->avctx->codec;
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    int ret;
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    if (!avpkt->size && !(codec->capabilities & CODEC_CAP_DELAY)) return 0;

    pthread_mutex_lock(&p->mutex);

    release_delayed_buffers(p);

    if (prev_thread) {
        int err;
        if (prev_thread->state == STATE_SETTING_UP) {
            pthread_mutex_lock(&prev_thread->progress_mutex);
            while (prev_thread->state == STATE_SETTING_UP)
                pthread_cond_wait(&prev_thread->progress_cond, &prev_thread->progress_mutex);
            pthread_mutex_unlock(&prev_thread->progress_mutex);
        }

        err = update_context_from_thread(p->avctx, prev_thread->avctx, 0);
        if (err) {
            pthread_mutex_unlock(&p->mutex);
            return err;
        }
    }

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    av_packet_free_side_data(&p->avpkt);
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    av_buffer_unref(&p->avpkt.buf);
    p->avpkt = *avpkt;
    if (avpkt->buf)
        p->avpkt.buf = av_buffer_ref(avpkt->buf);
    else {
        av_fast_malloc(&p->buf, &p->allocated_buf_size, avpkt->size + FF_INPUT_BUFFER_PADDING_SIZE);
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        if (!p->buf) {
            pthread_mutex_unlock(&p->mutex);
            return AVERROR(ENOMEM);
        }
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        p->avpkt.data = p->buf;
        memcpy(p->buf, avpkt->data, avpkt->size);
        memset(p->buf + avpkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
    }
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    if ((ret = av_copy_packet_side_data(&p->avpkt, avpkt)) < 0) {
        pthread_mutex_unlock(&p->mutex);
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        return ret;
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    }
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    p->state = STATE_SETTING_UP;
    pthread_cond_signal(&p->input_cond);
    pthread_mutex_unlock(&p->mutex);

    /*
     * If the client doesn't have a thread-safe get_buffer(),
     * then decoding threads call back to the main thread,
     * and it calls back to the client here.
     */

FF_DISABLE_DEPRECATION_WARNINGS
    if (!p->avctx->thread_safe_callbacks && (
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         p->avctx->get_format != avcodec_default_get_format ||
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#if FF_API_GET_BUFFER
         p->avctx->get_buffer ||
#endif
         p->avctx->get_buffer2 != avcodec_default_get_buffer2)) {
FF_ENABLE_DEPRECATION_WARNINGS
        while (p->state != STATE_SETUP_FINISHED && p->state != STATE_INPUT_READY) {
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            int call_done = 1;
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            pthread_mutex_lock(&p->progress_mutex);
            while (p->state == STATE_SETTING_UP)
                pthread_cond_wait(&p->progress_cond, &p->progress_mutex);

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            switch (p->state) {
            case STATE_GET_BUFFER:
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                p->result = ff_get_buffer(p->avctx, p->requested_frame, p->requested_flags);
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                break;
            case STATE_GET_FORMAT:
                p->result_format = p->avctx->get_format(p->avctx, p->available_formats);
                break;
            default:
                call_done = 0;
                break;
            }
            if (call_done) {
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                p->state  = STATE_SETTING_UP;
                pthread_cond_signal(&p->progress_cond);
            }
            pthread_mutex_unlock(&p->progress_mutex);
        }
    }

    fctx->prev_thread = p;
    fctx->next_decoding++;

    return 0;
}

int ff_thread_decode_frame(AVCodecContext *avctx,
                           AVFrame *picture, int *got_picture_ptr,
                           AVPacket *avpkt)
{
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    FrameThreadContext *fctx = avctx->internal->thread_ctx;
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    int finished = fctx->next_finished;
    PerThreadContext *p;
    int err;

    /*
     * Submit a packet to the next decoding thread.
     */

    p = &fctx->threads[fctx->next_decoding];
    err = update_context_from_user(p->avctx, avctx);
    if (err) return err;
    err = submit_packet(p, avpkt);
    if (err) return err;

    /*
     * If we're still receiving the initial packets, don't return a frame.
     */

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    if (fctx->next_decoding > (avctx->thread_count-1-(avctx->codec_id == AV_CODEC_ID_FFV1)))
        fctx->delaying = 0;
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    if (fctx->delaying) {
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        *got_picture_ptr=0;
        if (avpkt->size)
            return avpkt->size;
    }

    /*
     * Return the next available frame from the oldest thread.
     * If we're at the end of the stream, then we have to skip threads that
     * didn't output a frame, because we don't want to accidentally signal
     * EOF (avpkt->size == 0 && *got_picture_ptr == 0).
     */

    do {
        p = &fctx->threads[finished++];

        if (p->state != STATE_INPUT_READY) {
            pthread_mutex_lock(&p->progress_mutex);
            while (p->state != STATE_INPUT_READY)
                pthread_cond_wait(&p->output_cond, &p->progress_mutex);
            pthread_mutex_unlock(&p->progress_mutex);
        }

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        av_frame_move_ref(picture, p->frame);
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        *got_picture_ptr = p->got_frame;
        picture->pkt_dts = p->avpkt.dts;

        /*
         * A later call with avkpt->size == 0 may loop over all threads,
         * including this one, searching for a frame to return before being
         * stopped by the "finished != fctx->next_finished" condition.
         * Make sure we don't mistakenly return the same frame again.
         */
        p->got_frame = 0;

        if (finished >= avctx->thread_count) finished = 0;
    } while (!avpkt->size && !*got_picture_ptr && finished != fctx->next_finished);

    update_context_from_thread(avctx, p->avctx, 1);

    if (fctx->next_decoding >= avctx->thread_count) fctx->next_decoding = 0;

    fctx->next_finished = finished;

    /* return the size of the consumed packet if no error occurred */
    return (p->result >= 0) ? avpkt->size : p->result;
}

void ff_thread_report_progress(ThreadFrame *f, int n, int field)
{
    PerThreadContext *p;
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    volatile int *progress = f->progress ? (int*)f->progress->data : NULL;
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    if (!progress || progress[field] >= n) return;

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    p = f->owner->internal->thread_ctx;
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    if (f->owner->debug&FF_DEBUG_THREADS)
        av_log(f->owner, AV_LOG_DEBUG, "%p finished %d field %d\n", progress, n, field);

    pthread_mutex_lock(&p->progress_mutex);
    progress[field] = n;
    pthread_cond_broadcast(&p->progress_cond);
    pthread_mutex_unlock(&p->progress_mutex);
}

void ff_thread_await_progress(ThreadFrame *f, int n, int field)
{
    PerThreadContext *p;
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    volatile int *progress = f->progress ? (int*)f->progress->data : NULL;
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    if (!progress || progress[field] >= n) return;

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    p = f->owner->internal->thread_ctx;
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    if (f->owner->debug&FF_DEBUG_THREADS)
        av_log(f->owner, AV_LOG_DEBUG, "thread awaiting %d field %d from %p\n", n, field, progress);

    pthread_mutex_lock(&p->progress_mutex);
    while (progress[field] < n)
        pthread_cond_wait(&p->progress_cond, &p->progress_mutex);
    pthread_mutex_unlock(&p->progress_mutex);
}

void ff_thread_finish_setup(AVCodecContext *avctx) {
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    PerThreadContext *p = avctx->internal->thread_ctx;
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    if (!(avctx->active_thread_type&FF_THREAD_FRAME)) return;

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    if(p->state == STATE_SETUP_FINISHED){
        av_log(avctx, AV_LOG_WARNING, "Multiple ff_thread_finish_setup() calls\n");
    }

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    pthread_mutex_lock(&p->progress_mutex);
    p->state = STATE_SETUP_FINISHED;
    pthread_cond_broadcast(&p->progress_cond);
    pthread_mutex_unlock(&p->progress_mutex);
}

/// Waits for all threads to finish.
static void park_frame_worker_threads(FrameThreadContext *fctx, int thread_count)
{
    int i;

    for (i = 0; i < thread_count; i++) {
        PerThreadContext *p = &fctx->threads[i];

        if (p->state != STATE_INPUT_READY) {
            pthread_mutex_lock(&p->progress_mutex);
            while (p->state != STATE_INPUT_READY)
                pthread_cond_wait(&p->output_cond, &p->progress_mutex);
            pthread_mutex_unlock(&p->progress_mutex);
        }
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        p->got_frame = 0;
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    }
}

void ff_frame_thread_free(AVCodecContext *avctx, int thread_count)
{
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    FrameThreadContext *fctx = avctx->internal->thread_ctx;
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    const AVCodec *codec = avctx->codec;
    int i;

    park_frame_worker_threads(fctx, thread_count);

    if (fctx->prev_thread && fctx->prev_thread != fctx->threads)
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        if (update_context_from_thread(fctx->threads->avctx, fctx->prev_thread->avctx, 0) < 0) {
            av_log(avctx, AV_LOG_ERROR, "Final thread update failed\n");
            fctx->prev_thread->avctx->internal->is_copy = fctx->threads->avctx->internal->is_copy;
            fctx->threads->avctx->internal->is_copy = 1;
        }
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    fctx->die = 1;

    for (i = 0; i < thread_count; i++) {
        PerThreadContext *p = &fctx->threads[i];

        pthread_mutex_lock(&p->mutex);
        pthread_cond_signal(&p->input_cond);
        pthread_mutex_unlock(&p->mutex);

        if (p->thread_init)
            pthread_join(p->thread, NULL);
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        p->thread_init=0;
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        if (codec->close)
            codec->close(p->avctx);

        avctx->codec = NULL;

        release_delayed_buffers(p);
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        av_frame_free(&p->frame);
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    }

    for (i = 0; i < thread_count; i++) {
        PerThreadContext *p = &fctx->threads[i];

        pthread_mutex_destroy(&p->mutex);
        pthread_mutex_destroy(&p->progress_mutex);
        pthread_cond_destroy(&p->input_cond);
        pthread_cond_destroy(&p->progress_cond);
        pthread_cond_destroy(&p->output_cond);
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        av_packet_free_side_data(&p->avpkt);
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        av_buffer_unref(&p->avpkt.buf);
        av_freep(&p->buf);
        av_freep(&p->released_buffers);

        if (i) {
            av_freep(&p->avctx->priv_data);
            av_freep(&p->avctx->slice_offset);
        }

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        av_freep(&p->avctx->internal);
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        av_freep(&p->avctx);
    }

    av_freep(&fctx->threads);
    pthread_mutex_destroy(&fctx->buffer_mutex);
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    av_freep(&avctx->internal->thread_ctx);
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}

int ff_frame_thread_init(AVCodecContext *avctx)
{
    int thread_count = avctx->thread_count;
    const AVCodec *codec = avctx->codec;
    AVCodecContext *src = avctx;
    FrameThreadContext *fctx;
    int i, err = 0;

#if HAVE_W32THREADS
    w32thread_init();
#endif

    if (!thread_count) {
        int nb_cpus = av_cpu_count();
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        if ((avctx->debug & (FF_DEBUG_VIS_QP | FF_DEBUG_VIS_MB_TYPE)) || avctx->debug_mv)
            nb_cpus = 1;
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        // use number of cores + 1 as thread count if there is more than one
        if (nb_cpus > 1)
            thread_count = avctx->thread_count = FFMIN(nb_cpus + 1, MAX_AUTO_THREADS);
        else
            thread_count = avctx->thread_count = 1;
    }

    if (thread_count <= 1) {
        avctx->active_thread_type = 0;
        return 0;
    }

648
    avctx->internal->thread_ctx = fctx = av_mallocz(sizeof(FrameThreadContext));
649 650 651 652 653 654 655 656 657 658 659 660 661 662 663

    fctx->threads = av_mallocz(sizeof(PerThreadContext) * thread_count);
    pthread_mutex_init(&fctx->buffer_mutex, NULL);
    fctx->delaying = 1;

    for (i = 0; i < thread_count; i++) {
        AVCodecContext *copy = av_malloc(sizeof(AVCodecContext));
        PerThreadContext *p  = &fctx->threads[i];

        pthread_mutex_init(&p->mutex, NULL);
        pthread_mutex_init(&p->progress_mutex, NULL);
        pthread_cond_init(&p->input_cond, NULL);
        pthread_cond_init(&p->progress_cond, NULL);
        pthread_cond_init(&p->output_cond, NULL);

664 665 666
        p->frame = av_frame_alloc();
        if (!p->frame) {
            err = AVERROR(ENOMEM);
667
            av_freep(&copy);
668 669 670
            goto error;
        }

671 672 673 674 675 676 677 678 679 680
        p->parent = fctx;
        p->avctx  = copy;

        if (!copy) {
            err = AVERROR(ENOMEM);
            goto error;
        }

        *copy = *src;

681 682 683 684 685 686 687
        copy->internal = av_malloc(sizeof(AVCodecInternal));
        if (!copy->internal) {
            err = AVERROR(ENOMEM);
            goto error;
        }
        *copy->internal = *src->internal;
        copy->internal->thread_ctx = p;
688
        copy->internal->pkt = &p->avpkt;
689

690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
        if (!i) {
            src = copy;

            if (codec->init)
                err = codec->init(copy);

            update_context_from_thread(avctx, copy, 1);
        } else {
            copy->priv_data = av_malloc(codec->priv_data_size);
            if (!copy->priv_data) {
                err = AVERROR(ENOMEM);
                goto error;
            }
            memcpy(copy->priv_data, src->priv_data, codec->priv_data_size);
            copy->internal->is_copy = 1;

            if (codec->init_thread_copy)
                err = codec->init_thread_copy(copy);
        }

        if (err) goto error;

712 713 714 715
        err = AVERROR(pthread_create(&p->thread, NULL, frame_worker_thread, p));
        p->thread_init= !err;
        if(!p->thread_init)
            goto error;
716 717 718 719 720 721 722 723 724 725 726 727 728
    }

    return 0;

error:
    ff_frame_thread_free(avctx, i+1);

    return err;
}

void ff_thread_flush(AVCodecContext *avctx)
{
    int i;
729
    FrameThreadContext *fctx = avctx->internal->thread_ctx;
730

731
    if (!fctx) return;
732 733 734 735 736 737 738 739 740 741 742 743 744 745

    park_frame_worker_threads(fctx, avctx->thread_count);
    if (fctx->prev_thread) {
        if (fctx->prev_thread != &fctx->threads[0])
            update_context_from_thread(fctx->threads[0].avctx, fctx->prev_thread->avctx, 0);
    }

    fctx->next_decoding = fctx->next_finished = 0;
    fctx->delaying = 1;
    fctx->prev_thread = NULL;
    for (i = 0; i < avctx->thread_count; i++) {
        PerThreadContext *p = &fctx->threads[i];
        // Make sure decode flush calls with size=0 won't return old frames
        p->got_frame = 0;
746
        av_frame_unref(p->frame);
747 748

        release_delayed_buffers(p);
749 750 751

        if (avctx->codec->flush)
            avctx->codec->flush(p->avctx);
752 753 754
    }
}

755 756
int ff_thread_can_start_frame(AVCodecContext *avctx)
{
757
    PerThreadContext *p = avctx->internal->thread_ctx;
758 759 760 761 762 763 764 765
    if ((avctx->active_thread_type&FF_THREAD_FRAME) && p->state != STATE_SETTING_UP &&
        (avctx->codec->update_thread_context || !THREAD_SAFE_CALLBACKS(avctx))) {
        return 0;
    }
    return 1;
}

static int thread_get_buffer_internal(AVCodecContext *avctx, ThreadFrame *f, int flags)
766
{
767
    PerThreadContext *p = avctx->internal->thread_ctx;
768 769 770 771
    int err;

    f->owner = avctx;

772 773
    ff_init_buffer_info(avctx, f->f);

774 775 776 777
    if (!(avctx->active_thread_type & FF_THREAD_FRAME))
        return ff_get_buffer(avctx, f->f, flags);

    if (p->state != STATE_SETTING_UP &&
778
        (avctx->codec->update_thread_context || !THREAD_SAFE_CALLBACKS(avctx))) {
779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803
        av_log(avctx, AV_LOG_ERROR, "get_buffer() cannot be called after ff_thread_finish_setup()\n");
        return -1;
    }

    if (avctx->internal->allocate_progress) {
        int *progress;
        f->progress = av_buffer_alloc(2 * sizeof(int));
        if (!f->progress) {
            return AVERROR(ENOMEM);
        }
        progress = (int*)f->progress->data;

        progress[0] = progress[1] = -1;
    }

    pthread_mutex_lock(&p->parent->buffer_mutex);
FF_DISABLE_DEPRECATION_WARNINGS
    if (avctx->thread_safe_callbacks || (
#if FF_API_GET_BUFFER
        !avctx->get_buffer &&
#endif
        avctx->get_buffer2 == avcodec_default_get_buffer2)) {
FF_ENABLE_DEPRECATION_WARNINGS
        err = ff_get_buffer(avctx, f->f, flags);
    } else {
804
        pthread_mutex_lock(&p->progress_mutex);
805 806 807
        p->requested_frame = f->f;
        p->requested_flags = flags;
        p->state = STATE_GET_BUFFER;
808
        pthread_cond_broadcast(&p->progress_cond);
809 810 811 812 813 814 815 816 817

        while (p->state != STATE_SETTING_UP)
            pthread_cond_wait(&p->progress_cond, &p->progress_mutex);

        err = p->result;

        pthread_mutex_unlock(&p->progress_mutex);

    }
818
    if (!THREAD_SAFE_CALLBACKS(avctx) && !avctx->codec->update_thread_context)
819 820 821 822 823 824 825 826 827 828
        ff_thread_finish_setup(avctx);

    if (err)
        av_buffer_unref(&f->progress);

    pthread_mutex_unlock(&p->parent->buffer_mutex);

    return err;
}

829 830 831
enum AVPixelFormat ff_thread_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
{
    enum AVPixelFormat res;
832
    PerThreadContext *p = avctx->internal->thread_ctx;
833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862
    if (!(avctx->active_thread_type & FF_THREAD_FRAME) || avctx->thread_safe_callbacks ||
        avctx->get_format == avcodec_default_get_format)
        return avctx->get_format(avctx, fmt);
    if (p->state != STATE_SETTING_UP) {
        av_log(avctx, AV_LOG_ERROR, "get_format() cannot be called after ff_thread_finish_setup()\n");
        return -1;
    }
    pthread_mutex_lock(&p->progress_mutex);
    p->available_formats = fmt;
    p->state = STATE_GET_FORMAT;
    pthread_cond_broadcast(&p->progress_cond);

    while (p->state != STATE_SETTING_UP)
        pthread_cond_wait(&p->progress_cond, &p->progress_mutex);

    res = p->result_format;

    pthread_mutex_unlock(&p->progress_mutex);

    return res;
}

int ff_thread_get_buffer(AVCodecContext *avctx, ThreadFrame *f, int flags)
{
    int ret = thread_get_buffer_internal(avctx, f, flags);
    if (ret < 0)
        av_log(avctx, AV_LOG_ERROR, "thread_get_buffer() failed\n");
    return ret;
}

863 864
void ff_thread_release_buffer(AVCodecContext *avctx, ThreadFrame *f)
{
865
    PerThreadContext *p = avctx->internal->thread_ctx;
866 867 868 869 870 871 872 873 874 875 876 877
    FrameThreadContext *fctx;
    AVFrame *dst, *tmp;
FF_DISABLE_DEPRECATION_WARNINGS
    int can_direct_free = !(avctx->active_thread_type & FF_THREAD_FRAME) ||
                          avctx->thread_safe_callbacks                   ||
                          (
#if FF_API_GET_BUFFER
                           !avctx->get_buffer &&
#endif
                           avctx->get_buffer2 == avcodec_default_get_buffer2);
FF_ENABLE_DEPRECATION_WARNINGS

878
    if (!f->f || !f->f->buf[0])
879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
        return;

    if (avctx->debug & FF_DEBUG_BUFFERS)
        av_log(avctx, AV_LOG_DEBUG, "thread_release_buffer called on pic %p\n", f);

    av_buffer_unref(&f->progress);
    f->owner    = NULL;

    if (can_direct_free) {
        av_frame_unref(f->f);
        return;
    }

    fctx = p->parent;
    pthread_mutex_lock(&fctx->buffer_mutex);

    if (p->num_released_buffers + 1 >= INT_MAX / sizeof(*p->released_buffers))
        goto fail;
    tmp = av_fast_realloc(p->released_buffers, &p->released_buffers_allocated,
                          (p->num_released_buffers + 1) *
                          sizeof(*p->released_buffers));
    if (!tmp)
        goto fail;
    p->released_buffers = tmp;

    dst = &p->released_buffers[p->num_released_buffers];
    av_frame_move_ref(dst, f->f);

    p->num_released_buffers++;

fail:
    pthread_mutex_unlock(&fctx->buffer_mutex);
}