diff options
author | Anton Khirnov <anton@khirnov.net> | 2016-10-19 22:05:22 +0300 |
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committer | Anton Khirnov <anton@khirnov.net> | 2016-11-02 12:16:04 +0300 |
commit | 7b1f03477f1a43d2261fbd83e50a4ad90c7f806d (patch) | |
tree | cc6c48d43c5abd69b99baeeb9cde003a76a0180f /doc/examples/encode_video.c | |
parent | 90265814f993098d79b0a0f40745ecdb403fbf56 (diff) |
examples/avcodec: split the remaining two examples into separate files
Diffstat (limited to 'doc/examples/encode_video.c')
-rw-r--r-- | doc/examples/encode_video.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/doc/examples/encode_video.c b/doc/examples/encode_video.c new file mode 100644 index 0000000000..ca93472920 --- /dev/null +++ b/doc/examples/encode_video.c @@ -0,0 +1,164 @@ +/* + * copyright (c) 2001 Fabrice Bellard + * + * This file is part of Libav. + * + * Libav is free software; you can redistribute it and/or + * 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. + * + * Libav is distributed in the hope that it will be useful, + * 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 + * License along with Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * video encoding with libavcodec API example + * + * @example encode_video.c + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "libavcodec/avcodec.h" + +#include "libavutil/frame.h" +#include "libavutil/imgutils.h" + +int main(int argc, char **argv) +{ + const char *filename; + AVCodec *codec; + AVCodecContext *c= NULL; + int i, ret, x, y, got_output; + FILE *f; + AVFrame *picture; + AVPacket pkt; + uint8_t endcode[] = { 0, 0, 1, 0xb7 }; + + if (argc <= 1) { + fprintf(stderr, "Usage: %s <output file>\n", argv[0]); + exit(0); + } + filename = argv[1]; + + avcodec_register_all(); + + /* find the mpeg1video encoder */ + codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO); + if (!codec) { + fprintf(stderr, "codec not found\n"); + exit(1); + } + + c = avcodec_alloc_context3(codec); + picture = av_frame_alloc(); + + /* put sample parameters */ + c->bit_rate = 400000; + /* resolution must be a multiple of two */ + c->width = 352; + c->height = 288; + /* frames per second */ + c->time_base= (AVRational){1,25}; + c->gop_size = 10; /* emit one intra frame every ten frames */ + c->max_b_frames=1; + c->pix_fmt = AV_PIX_FMT_YUV420P; + + /* open it */ + if (avcodec_open2(c, codec, NULL) < 0) { + fprintf(stderr, "could not open codec\n"); + exit(1); + } + + f = fopen(filename, "wb"); + if (!f) { + fprintf(stderr, "could not open %s\n", filename); + exit(1); + } + + ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height, + c->pix_fmt, 32); + if (ret < 0) { + fprintf(stderr, "could not alloc raw picture buffer\n"); + exit(1); + } + picture->format = c->pix_fmt; + picture->width = c->width; + picture->height = c->height; + + /* encode 1 second of video */ + for(i=0;i<25;i++) { + av_init_packet(&pkt); + pkt.data = NULL; // packet data will be allocated by the encoder + pkt.size = 0; + + fflush(stdout); + /* prepare a dummy image */ + /* Y */ + for(y=0;y<c->height;y++) { + for(x=0;x<c->width;x++) { + picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3; + } + } + + /* Cb and Cr */ + for(y=0;y<c->height/2;y++) { + for(x=0;x<c->width/2;x++) { + picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2; + picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5; + } + } + + picture->pts = i; + + /* encode the image */ + ret = avcodec_encode_video2(c, &pkt, picture, &got_output); + if (ret < 0) { + fprintf(stderr, "error encoding frame\n"); + exit(1); + } + + if (got_output) { + printf("encoding frame %3d (size=%5d)\n", i, pkt.size); + fwrite(pkt.data, 1, pkt.size, f); + av_packet_unref(&pkt); + } + } + + /* get the delayed frames */ + for (got_output = 1; got_output; i++) { + fflush(stdout); + + ret = avcodec_encode_video2(c, &pkt, NULL, &got_output); + if (ret < 0) { + fprintf(stderr, "error encoding frame\n"); + exit(1); + } + + if (got_output) { + printf("encoding frame %3d (size=%5d)\n", i, pkt.size); + fwrite(pkt.data, 1, pkt.size, f); + av_packet_unref(&pkt); + } + } + + /* add sequence end code to have a real MPEG file */ + fwrite(endcode, 1, sizeof(endcode), f); + fclose(f); + + avcodec_free_context(&c); + av_freep(&picture->data[0]); + av_frame_free(&picture); + + return 0; +} |