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https://github.com/FFmpeg/FFmpeg.git
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59ab9e8ba1
AVPackets on stack are discouraged.
176 lines
4.4 KiB
C
176 lines
4.4 KiB
C
/*
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* copyright (c) 2001 Fabrice Bellard
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* video encoding with libavcodec API example
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*
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* @example encode_video.c
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "libavcodec/avcodec.h"
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#include "libavutil/frame.h"
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#include "libavutil/imgutils.h"
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static void encode(AVCodecContext *enc_ctx, AVFrame *frame, AVPacket *pkt,
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FILE *outfile)
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{
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int ret;
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/* send the frame to the encoder */
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ret = avcodec_send_frame(enc_ctx, frame);
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if (ret < 0) {
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fprintf(stderr, "error sending a frame for encoding\n");
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exit(1);
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}
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while (ret >= 0) {
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ret = avcodec_receive_packet(enc_ctx, pkt);
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if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
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return;
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else if (ret < 0) {
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fprintf(stderr, "error during encoding\n");
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exit(1);
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}
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printf("encoded frame %3"PRId64" (size=%5d)\n", pkt->pts, pkt->size);
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fwrite(pkt->data, 1, pkt->size, outfile);
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av_packet_unref(pkt);
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}
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}
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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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const AVCodec *codec;
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AVCodecContext *c= NULL;
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int i, ret, x, y;
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FILE *f;
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AVFrame *picture;
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AVPacket *pkt;
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uint8_t endcode[] = { 0, 0, 1, 0xb7 };
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if (argc <= 1) {
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fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
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exit(0);
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}
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filename = argv[1];
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avcodec_register_all();
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/* find the mpeg1video encoder */
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codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
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if (!codec) {
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fprintf(stderr, "codec not found\n");
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exit(1);
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}
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c = avcodec_alloc_context3(codec);
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picture = av_frame_alloc();
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pkt = av_packet_alloc();
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if (!pkt)
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exit(1);
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/* put sample parameters */
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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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/* frames per second */
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c->time_base = (AVRational){1, 25};
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c->framerate = (AVRational){25, 1};
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c->gop_size = 10; /* emit one intra frame every ten frames */
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c->max_b_frames=1;
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c->pix_fmt = AV_PIX_FMT_YUV420P;
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/* open it */
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if (avcodec_open2(c, codec, NULL) < 0) {
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fprintf(stderr, "could not open codec\n");
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exit(1);
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}
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f = fopen(filename, "wb");
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if (!f) {
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fprintf(stderr, "could not open %s\n", filename);
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exit(1);
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}
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picture->format = c->pix_fmt;
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picture->width = c->width;
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picture->height = c->height;
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ret = av_frame_get_buffer(picture, 32);
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if (ret < 0) {
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fprintf(stderr, "could not alloc the frame data\n");
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exit(1);
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}
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/* encode 1 second of video */
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for(i=0;i<25;i++) {
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fflush(stdout);
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/* make sure the frame data is writable */
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ret = av_frame_make_writable(picture);
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if (ret < 0)
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exit(1);
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/* prepare a dummy image */
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/* Y */
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for(y=0;y<c->height;y++) {
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for(x=0;x<c->width;x++) {
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picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
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}
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}
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/* Cb and Cr */
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for(y=0;y<c->height/2;y++) {
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for(x=0;x<c->width/2;x++) {
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picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
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picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
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}
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}
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picture->pts = i;
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/* encode the image */
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encode(c, picture, pkt, f);
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}
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/* flush the encoder */
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encode(c, NULL, pkt, f);
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/* add sequence end code to have a real MPEG file */
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fwrite(endcode, 1, sizeof(endcode), f);
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fclose(f);
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avcodec_free_context(&c);
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av_frame_free(&picture);
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av_packet_free(&pkt);
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return 0;
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}
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