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2aa2b4ac65
Allows to encode to output in case the destination sample format is different from AV_SAMPLE_FMT_S16.
565 lines
18 KiB
C
565 lines
18 KiB
C
/*
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* Copyright (c) 2003 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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/**
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* @file
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* libavformat API example.
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*
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* Output a media file in any supported libavformat format.
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* The default codecs are used.
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* @example doc/examples/muxing.c
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*/
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include <math.h>
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#include <libavutil/opt.h>
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#include <libavutil/mathematics.h>
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#include <libavformat/avformat.h>
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#include <libswscale/swscale.h>
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#include <libswresample/swresample.h>
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/* 5 seconds stream duration */
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#define STREAM_DURATION 200.0
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#define STREAM_FRAME_RATE 25 /* 25 images/s */
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#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
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#define STREAM_PIX_FMT AV_PIX_FMT_YUV420P /* default pix_fmt */
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static int sws_flags = SWS_BICUBIC;
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/* Add an output stream. */
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static AVStream *add_stream(AVFormatContext *oc, AVCodec **codec,
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enum AVCodecID codec_id)
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{
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AVCodecContext *c;
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AVStream *st;
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/* find the encoder */
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*codec = avcodec_find_encoder(codec_id);
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if (!(*codec)) {
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fprintf(stderr, "Could not find encoder for '%s'\n",
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avcodec_get_name(codec_id));
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exit(1);
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}
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st = avformat_new_stream(oc, *codec);
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if (!st) {
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fprintf(stderr, "Could not allocate stream\n");
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exit(1);
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}
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st->id = oc->nb_streams-1;
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c = st->codec;
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switch ((*codec)->type) {
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case AVMEDIA_TYPE_AUDIO:
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c->sample_fmt = AV_SAMPLE_FMT_FLTP;
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c->bit_rate = 64000;
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c->sample_rate = 44100;
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c->channels = 2;
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break;
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case AVMEDIA_TYPE_VIDEO:
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c->codec_id = codec_id;
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c->bit_rate = 400000;
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/* Resolution must be a multiple of two. */
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c->width = 352;
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c->height = 288;
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/* timebase: This is the fundamental unit of time (in seconds) in terms
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* of which frame timestamps are represented. For fixed-fps content,
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* timebase should be 1/framerate and timestamp increments should be
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* identical to 1. */
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c->time_base.den = STREAM_FRAME_RATE;
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c->time_base.num = 1;
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c->gop_size = 12; /* emit one intra frame every twelve frames at most */
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c->pix_fmt = STREAM_PIX_FMT;
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if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
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/* just for testing, we also add B frames */
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c->max_b_frames = 2;
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}
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if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
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/* Needed to avoid using macroblocks in which some coeffs overflow.
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* This does not happen with normal video, it just happens here as
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* the motion of the chroma plane does not match the luma plane. */
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c->mb_decision = 2;
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}
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break;
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default:
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break;
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}
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/* Some formats want stream headers to be separate. */
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if (oc->oformat->flags & AVFMT_GLOBALHEADER)
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c->flags |= CODEC_FLAG_GLOBAL_HEADER;
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return st;
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}
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/**************************************************************/
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/* audio output */
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static float t, tincr, tincr2;
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static uint8_t **src_samples_data;
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static int src_samples_linesize;
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static int src_nb_samples;
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static int max_dst_nb_samples;
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uint8_t **dst_samples_data;
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int dst_samples_linesize;
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int dst_samples_size;
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struct SwrContext *swr_ctx = NULL;
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static void open_audio(AVFormatContext *oc, AVCodec *codec, AVStream *st)
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{
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AVCodecContext *c;
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int ret;
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c = st->codec;
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/* open it */
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ret = avcodec_open2(c, codec, NULL);
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if (ret < 0) {
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fprintf(stderr, "Could not open audio codec: %s\n", av_err2str(ret));
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exit(1);
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}
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/* init signal generator */
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t = 0;
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tincr = 2 * M_PI * 110.0 / c->sample_rate;
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/* increment frequency by 110 Hz per second */
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tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
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src_nb_samples = c->codec->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE ?
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10000 : c->frame_size;
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ret = av_samples_alloc_array_and_samples(&src_samples_data, &src_samples_linesize, c->channels,
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src_nb_samples, c->sample_fmt, 0);
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if (ret < 0) {
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fprintf(stderr, "Could not allocate source samples\n");
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exit(1);
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}
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/* create resampler context */
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if (c->sample_fmt != AV_SAMPLE_FMT_S16) {
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swr_ctx = swr_alloc();
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if (!swr_ctx) {
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fprintf(stderr, "Could not allocate resampler context\n");
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exit(1);
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}
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/* set options */
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av_opt_set_int (swr_ctx, "in_channel_count", c->channels, 0);
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av_opt_set_int (swr_ctx, "in_sample_rate", c->sample_rate, 0);
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av_opt_set_sample_fmt(swr_ctx, "in_sample_fmt", AV_SAMPLE_FMT_S16, 0);
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av_opt_set_int (swr_ctx, "out_channel_count", c->channels, 0);
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av_opt_set_int (swr_ctx, "out_sample_rate", c->sample_rate, 0);
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av_opt_set_sample_fmt(swr_ctx, "out_sample_fmt", c->sample_fmt, 0);
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/* initialize the resampling context */
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if ((ret = swr_init(swr_ctx)) < 0) {
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fprintf(stderr, "Failed to initialize the resampling context\n");
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exit(1);
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}
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}
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/* compute the number of converted samples: buffering is avoided
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* ensuring that the output buffer will contain at least all the
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* converted input samples */
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max_dst_nb_samples = src_nb_samples;
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ret = av_samples_alloc_array_and_samples(&dst_samples_data, &dst_samples_linesize, c->channels,
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max_dst_nb_samples, c->sample_fmt, 0);
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if (ret < 0) {
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fprintf(stderr, "Could not allocate destination samples\n");
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exit(1);
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}
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dst_samples_size = av_samples_get_buffer_size(NULL, c->channels, max_dst_nb_samples,
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c->sample_fmt, 0);
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}
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/* Prepare a 16 bit dummy audio frame of 'frame_size' samples and
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* 'nb_channels' channels. */
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static void get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
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{
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int j, i, v;
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int16_t *q;
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q = samples;
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for (j = 0; j < frame_size; j++) {
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v = (int)(sin(t) * 10000);
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for (i = 0; i < nb_channels; i++)
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*q++ = v;
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t += tincr;
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tincr += tincr2;
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}
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}
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static void write_audio_frame(AVFormatContext *oc, AVStream *st)
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{
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AVCodecContext *c;
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AVPacket pkt = { 0 }; // data and size must be 0;
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AVFrame *frame = avcodec_alloc_frame();
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int got_packet, ret, dst_nb_samples;
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av_init_packet(&pkt);
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c = st->codec;
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get_audio_frame((int16_t *)src_samples_data[0], src_nb_samples, c->channels);
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/* convert samples from native format to destination codec format, using the resampler */
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if (swr_ctx) {
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/* compute destination number of samples */
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dst_nb_samples = av_rescale_rnd(swr_get_delay(swr_ctx, c->sample_rate) + src_nb_samples,
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c->sample_rate, c->sample_rate, AV_ROUND_UP);
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if (dst_nb_samples > max_dst_nb_samples) {
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av_free(dst_samples_data[0]);
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ret = av_samples_alloc(dst_samples_data, &dst_samples_linesize, c->channels,
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dst_nb_samples, c->sample_fmt, 0);
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if (ret < 0)
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exit(1);
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max_dst_nb_samples = dst_nb_samples;
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dst_samples_size = av_samples_get_buffer_size(NULL, c->channels, dst_nb_samples,
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c->sample_fmt, 0);
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}
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/* convert to destination format */
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ret = swr_convert(swr_ctx,
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dst_samples_data, dst_nb_samples,
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(const uint8_t **)src_samples_data, src_nb_samples);
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if (ret < 0) {
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fprintf(stderr, "Error while converting\n");
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exit(1);
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}
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} else {
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dst_samples_data[0] = src_samples_data[0];
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dst_nb_samples = src_nb_samples;
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}
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frame->nb_samples = dst_nb_samples;
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avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
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dst_samples_data[0], dst_samples_size, 0);
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ret = avcodec_encode_audio2(c, &pkt, frame, &got_packet);
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if (ret < 0) {
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fprintf(stderr, "Error encoding audio frame: %s\n", av_err2str(ret));
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exit(1);
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}
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if (!got_packet)
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return;
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pkt.stream_index = st->index;
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/* Write the compressed frame to the media file. */
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ret = av_interleaved_write_frame(oc, &pkt);
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if (ret != 0) {
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fprintf(stderr, "Error while writing audio frame: %s\n",
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av_err2str(ret));
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exit(1);
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}
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avcodec_free_frame(&frame);
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}
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static void close_audio(AVFormatContext *oc, AVStream *st)
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{
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avcodec_close(st->codec);
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av_free(src_samples_data[0]);
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av_free(dst_samples_data[0]);
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}
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/**************************************************************/
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/* video output */
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static AVFrame *frame;
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static AVPicture src_picture, dst_picture;
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static int frame_count;
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static void open_video(AVFormatContext *oc, AVCodec *codec, AVStream *st)
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{
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int ret;
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AVCodecContext *c = st->codec;
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/* open the codec */
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ret = avcodec_open2(c, codec, NULL);
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if (ret < 0) {
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fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
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exit(1);
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}
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/* allocate and init a re-usable frame */
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frame = avcodec_alloc_frame();
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if (!frame) {
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fprintf(stderr, "Could not allocate video frame\n");
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exit(1);
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}
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/* Allocate the encoded raw picture. */
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ret = avpicture_alloc(&dst_picture, c->pix_fmt, c->width, c->height);
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if (ret < 0) {
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fprintf(stderr, "Could not allocate picture: %s\n", av_err2str(ret));
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exit(1);
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}
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/* If the output format is not YUV420P, then a temporary YUV420P
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* picture is needed too. It is then converted to the required
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* output format. */
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if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
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ret = avpicture_alloc(&src_picture, AV_PIX_FMT_YUV420P, c->width, c->height);
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if (ret < 0) {
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fprintf(stderr, "Could not allocate temporary picture: %s\n",
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av_err2str(ret));
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exit(1);
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}
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}
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/* copy data and linesize picture pointers to frame */
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*((AVPicture *)frame) = dst_picture;
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}
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/* Prepare a dummy image. */
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static void fill_yuv_image(AVPicture *pict, int frame_index,
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int width, int height)
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{
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int x, y, i;
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i = frame_index;
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/* Y */
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for (y = 0; y < height; y++)
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for (x = 0; x < width; x++)
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pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
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/* Cb and Cr */
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for (y = 0; y < height / 2; y++) {
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for (x = 0; x < width / 2; x++) {
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pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
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pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
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}
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}
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}
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static void write_video_frame(AVFormatContext *oc, AVStream *st)
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{
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int ret;
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static struct SwsContext *sws_ctx;
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AVCodecContext *c = st->codec;
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if (frame_count >= STREAM_NB_FRAMES) {
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/* No more frames to compress. The codec has a latency of a few
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* frames if using B-frames, so we get the last frames by
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* passing the same picture again. */
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} else {
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if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
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/* as we only generate a YUV420P picture, we must convert it
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* to the codec pixel format if needed */
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if (!sws_ctx) {
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sws_ctx = sws_getContext(c->width, c->height, AV_PIX_FMT_YUV420P,
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c->width, c->height, c->pix_fmt,
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sws_flags, NULL, NULL, NULL);
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if (!sws_ctx) {
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fprintf(stderr,
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"Could not initialize the conversion context\n");
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exit(1);
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}
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}
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fill_yuv_image(&src_picture, frame_count, c->width, c->height);
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sws_scale(sws_ctx,
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(const uint8_t * const *)src_picture.data, src_picture.linesize,
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0, c->height, dst_picture.data, dst_picture.linesize);
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} else {
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fill_yuv_image(&dst_picture, frame_count, c->width, c->height);
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}
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}
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if (oc->oformat->flags & AVFMT_RAWPICTURE) {
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/* Raw video case - directly store the picture in the packet */
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AVPacket pkt;
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av_init_packet(&pkt);
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pkt.flags |= AV_PKT_FLAG_KEY;
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pkt.stream_index = st->index;
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pkt.data = dst_picture.data[0];
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pkt.size = sizeof(AVPicture);
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ret = av_interleaved_write_frame(oc, &pkt);
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} else {
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AVPacket pkt = { 0 };
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int got_packet;
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av_init_packet(&pkt);
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/* encode the image */
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ret = avcodec_encode_video2(c, &pkt, frame, &got_packet);
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if (ret < 0) {
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fprintf(stderr, "Error encoding video frame: %s\n", av_err2str(ret));
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exit(1);
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}
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/* If size is zero, it means the image was buffered. */
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if (!ret && got_packet && pkt.size) {
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pkt.stream_index = st->index;
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/* Write the compressed frame to the media file. */
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ret = av_interleaved_write_frame(oc, &pkt);
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} else {
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ret = 0;
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}
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}
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if (ret != 0) {
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fprintf(stderr, "Error while writing video frame: %s\n", av_err2str(ret));
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exit(1);
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}
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frame_count++;
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}
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static void close_video(AVFormatContext *oc, AVStream *st)
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{
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avcodec_close(st->codec);
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av_free(src_picture.data[0]);
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av_free(dst_picture.data[0]);
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av_free(frame);
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}
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/**************************************************************/
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/* media file output */
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int main(int argc, char **argv)
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{
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const char *filename;
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AVOutputFormat *fmt;
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AVFormatContext *oc;
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AVStream *audio_st, *video_st;
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AVCodec *audio_codec, *video_codec;
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double audio_time, video_time;
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int ret;
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/* Initialize libavcodec, and register all codecs and formats. */
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av_register_all();
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if (argc != 2) {
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printf("usage: %s output_file\n"
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"API example program to output a media file with libavformat.\n"
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"This program generates a synthetic audio and video stream, encodes and\n"
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"muxes them into a file named output_file.\n"
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"The output format is automatically guessed according to the file extension.\n"
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"Raw images can also be output by using '%%d' in the filename.\n"
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"\n", argv[0]);
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return 1;
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}
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filename = argv[1];
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/* allocate the output media context */
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avformat_alloc_output_context2(&oc, NULL, NULL, filename);
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if (!oc) {
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printf("Could not deduce output format from file extension: using MPEG.\n");
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avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
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}
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if (!oc) {
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return 1;
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}
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fmt = oc->oformat;
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/* Add the audio and video streams using the default format codecs
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* and initialize the codecs. */
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video_st = NULL;
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audio_st = NULL;
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if (fmt->video_codec != AV_CODEC_ID_NONE) {
|
|
video_st = add_stream(oc, &video_codec, fmt->video_codec);
|
|
}
|
|
if (fmt->audio_codec != AV_CODEC_ID_NONE) {
|
|
audio_st = add_stream(oc, &audio_codec, fmt->audio_codec);
|
|
}
|
|
|
|
/* Now that all the parameters are set, we can open the audio and
|
|
* video codecs and allocate the necessary encode buffers. */
|
|
if (video_st)
|
|
open_video(oc, video_codec, video_st);
|
|
if (audio_st)
|
|
open_audio(oc, audio_codec, audio_st);
|
|
|
|
av_dump_format(oc, 0, filename, 1);
|
|
|
|
/* open the output file, if needed */
|
|
if (!(fmt->flags & AVFMT_NOFILE)) {
|
|
ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
|
|
if (ret < 0) {
|
|
fprintf(stderr, "Could not open '%s': %s\n", filename,
|
|
av_err2str(ret));
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/* Write the stream header, if any. */
|
|
ret = avformat_write_header(oc, NULL);
|
|
if (ret < 0) {
|
|
fprintf(stderr, "Error occurred when opening output file: %s\n",
|
|
av_err2str(ret));
|
|
return 1;
|
|
}
|
|
|
|
if (frame)
|
|
frame->pts = 0;
|
|
for (;;) {
|
|
/* Compute current audio and video time. */
|
|
audio_time = audio_st ? audio_st->pts.val * av_q2d(audio_st->time_base) : 0.0;
|
|
video_time = video_st ? video_st->pts.val * av_q2d(video_st->time_base) : 0.0;
|
|
|
|
if ((!audio_st || audio_time >= STREAM_DURATION) &&
|
|
(!video_st || video_time >= STREAM_DURATION))
|
|
break;
|
|
|
|
/* write interleaved audio and video frames */
|
|
if (!video_st || (video_st && audio_st && audio_time < video_time)) {
|
|
write_audio_frame(oc, audio_st);
|
|
} else {
|
|
write_video_frame(oc, video_st);
|
|
frame->pts += av_rescale_q(1, video_st->codec->time_base, video_st->time_base);
|
|
}
|
|
}
|
|
|
|
/* Write the trailer, if any. The trailer must be written before you
|
|
* close the CodecContexts open when you wrote the header; otherwise
|
|
* av_write_trailer() may try to use memory that was freed on
|
|
* av_codec_close(). */
|
|
av_write_trailer(oc);
|
|
|
|
/* Close each codec. */
|
|
if (video_st)
|
|
close_video(oc, video_st);
|
|
if (audio_st)
|
|
close_audio(oc, audio_st);
|
|
|
|
if (!(fmt->flags & AVFMT_NOFILE))
|
|
/* Close the output file. */
|
|
avio_close(oc->pb);
|
|
|
|
/* free the stream */
|
|
avformat_free_context(oc);
|
|
|
|
return 0;
|
|
}
|