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author | Michael Niedermayer <michaelni@gmx.at> | 2011-10-11 22:13:02 +0200 |
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committer | Michael Niedermayer <michaelni@gmx.at> | 2011-10-11 22:16:04 +0200 |
commit | be5ac961e0a087a5a420a0477f8861dd05d0b9b7 (patch) | |
tree | 805ab14b05ca09b4782c6b9d8b5b596d27c38bf8 /doc/examples/encoding.c | |
parent | f8e98061ecc7301c8e1f5b7b83344fa64b483e5c (diff) | |
download | ffmpeg-be5ac961e0a087a5a420a0477f8861dd05d0b9b7.tar.gz |
examples/encoding: rename to decoding_encoding.c as the file is an example for both.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'doc/examples/encoding.c')
-rw-r--r-- | doc/examples/encoding.c | 458 |
1 files changed, 0 insertions, 458 deletions
diff --git a/doc/examples/encoding.c b/doc/examples/encoding.c deleted file mode 100644 index cd968dbf75..0000000000 --- a/doc/examples/encoding.c +++ /dev/null @@ -1,458 +0,0 @@ -/* - * Copyright (c) 2001 Fabrice Bellard - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - */ - -/** - * @file - * libavcodec API use example. - * - * Note that libavcodec only handles codecs (mpeg, mpeg4, etc...), - * not file formats (avi, vob, mp4, mov, mkv, mxf, flv, mpegts, mpegps, etc...). See library 'libavformat' for the - * format handling - */ - -#include "libavcodec/avcodec.h" -#include "libavutil/mathematics.h" - -#define INBUF_SIZE 4096 -#define AUDIO_INBUF_SIZE 20480 -#define AUDIO_REFILL_THRESH 4096 - -/* - * Audio encoding example - */ -static void audio_encode_example(const char *filename) -{ - AVCodec *codec; - AVCodecContext *c= NULL; - int frame_size, i, j, out_size, outbuf_size; - FILE *f; - short *samples; - float t, tincr; - uint8_t *outbuf; - - printf("Audio encoding\n"); - - /* find the MP2 encoder */ - codec = avcodec_find_encoder(CODEC_ID_MP2); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } - - c = avcodec_alloc_context3(codec); - - /* put sample parameters */ - c->bit_rate = 64000; - c->sample_rate = 44100; - c->channels = 2; - c->sample_fmt = AV_SAMPLE_FMT_S16; - - /* open it */ - if (avcodec_open(c, codec) < 0) { - fprintf(stderr, "could not open codec\n"); - exit(1); - } - - /* the codec gives us the frame size, in samples */ - frame_size = c->frame_size; - samples = malloc(frame_size * 2 * c->channels); - outbuf_size = 10000; - outbuf = malloc(outbuf_size); - - f = fopen(filename, "wb"); - if (!f) { - fprintf(stderr, "could not open %s\n", filename); - exit(1); - } - - /* encode a single tone sound */ - t = 0; - tincr = 2 * M_PI * 440.0 / c->sample_rate; - for(i=0;i<200;i++) { - for(j=0;j<frame_size;j++) { - samples[2*j] = (int)(sin(t) * 10000); - samples[2*j+1] = samples[2*j]; - t += tincr; - } - /* encode the samples */ - out_size = avcodec_encode_audio(c, outbuf, outbuf_size, samples); - fwrite(outbuf, 1, out_size, f); - } - fclose(f); - free(outbuf); - free(samples); - - avcodec_close(c); - av_free(c); -} - -/* - * Audio decoding. - */ -static void audio_decode_example(const char *outfilename, const char *filename) -{ - AVCodec *codec; - AVCodecContext *c= NULL; - int out_size, len; - FILE *f, *outfile; - uint8_t *outbuf; - uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; - AVPacket avpkt; - - av_init_packet(&avpkt); - - printf("Audio decoding\n"); - - /* find the mpeg audio decoder */ - codec = avcodec_find_decoder(CODEC_ID_MP2); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } - - c = avcodec_alloc_context3(codec); - - /* open it */ - if (avcodec_open(c, codec) < 0) { - fprintf(stderr, "could not open codec\n"); - exit(1); - } - - outbuf = malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE); - - f = fopen(filename, "rb"); - if (!f) { - fprintf(stderr, "could not open %s\n", filename); - exit(1); - } - outfile = fopen(outfilename, "wb"); - if (!outfile) { - av_free(c); - exit(1); - } - - /* decode until eof */ - avpkt.data = inbuf; - avpkt.size = fread(inbuf, 1, AUDIO_INBUF_SIZE, f); - - while (avpkt.size > 0) { - out_size = AVCODEC_MAX_AUDIO_FRAME_SIZE; - len = avcodec_decode_audio3(c, (short *)outbuf, &out_size, &avpkt); - if (len < 0) { - fprintf(stderr, "Error while decoding\n"); - exit(1); - } - if (out_size > 0) { - /* if a frame has been decoded, output it */ - fwrite(outbuf, 1, out_size, outfile); - } - avpkt.size -= len; - avpkt.data += len; - if (avpkt.size < AUDIO_REFILL_THRESH) { - /* Refill the input buffer, to avoid trying to decode - * incomplete frames. Instead of this, one could also use - * a parser, or use a proper container format through - * libavformat. */ - memmove(inbuf, avpkt.data, avpkt.size); - avpkt.data = inbuf; - len = fread(avpkt.data + avpkt.size, 1, - AUDIO_INBUF_SIZE - avpkt.size, f); - if (len > 0) - avpkt.size += len; - } - } - - fclose(outfile); - fclose(f); - free(outbuf); - - avcodec_close(c); - av_free(c); -} - -/* - * Video encoding example - */ -static void video_encode_example(const char *filename) -{ - AVCodec *codec; - AVCodecContext *c= NULL; - int i, out_size, size, x, y, outbuf_size; - FILE *f; - AVFrame *picture; - uint8_t *outbuf; - - printf("Video encoding\n"); - - /* find the mpeg1 video encoder */ - codec = avcodec_find_encoder(CODEC_ID_MPEG1VIDEO); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } - - c = avcodec_alloc_context3(codec); - picture= avcodec_alloc_frame(); - - /* 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 = PIX_FMT_YUV420P; - - /* open it */ - if (avcodec_open(c, codec) < 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); - } - - /* alloc image and output buffer */ - outbuf_size = 100000; - outbuf = malloc(outbuf_size); - - /* the image can be allocated by any means and av_image_alloc() is - * just the most convenient way if av_malloc() is to be used */ - av_image_alloc(picture->data, picture->linesize, - c->width, c->height, c->pix_fmt, 1); - - /* encode 1 second of video */ - for(i=0;i<25;i++) { - 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; - } - } - - /* encode the image */ - out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture); - printf("encoding frame %3d (size=%5d)\n", i, out_size); - fwrite(outbuf, 1, out_size, f); - } - - /* get the delayed frames */ - for(; out_size; i++) { - fflush(stdout); - - out_size = avcodec_encode_video(c, outbuf, outbuf_size, NULL); - printf("write frame %3d (size=%5d)\n", i, out_size); - fwrite(outbuf, 1, out_size, f); - } - - /* add sequence end code to have a real mpeg file */ - outbuf[0] = 0x00; - outbuf[1] = 0x00; - outbuf[2] = 0x01; - outbuf[3] = 0xb7; - fwrite(outbuf, 1, 4, f); - fclose(f); - free(outbuf); - - avcodec_close(c); - av_free(c); - av_free(picture->data[0]); - av_free(picture); - printf("\n"); -} - -/* - * Video decoding example - */ - -static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize, - char *filename) -{ - FILE *f; - int i; - - f=fopen(filename,"w"); - fprintf(f,"P5\n%d %d\n%d\n",xsize,ysize,255); - for(i=0;i<ysize;i++) - fwrite(buf + i * wrap,1,xsize,f); - fclose(f); -} - -static void video_decode_example(const char *outfilename, const char *filename) -{ - AVCodec *codec; - AVCodecContext *c= NULL; - int frame, got_picture, len; - FILE *f; - AVFrame *picture; - uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; - char buf[1024]; - AVPacket avpkt; - - av_init_packet(&avpkt); - - /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ - memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); - - printf("Video decoding\n"); - - /* find the mpeg1 video decoder */ - codec = avcodec_find_decoder(CODEC_ID_MPEG1VIDEO); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } - - c = avcodec_alloc_context3(codec); - picture= avcodec_alloc_frame(); - - if(codec->capabilities&CODEC_CAP_TRUNCATED) - c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ - - /* For some codecs, such as msmpeg4 and mpeg4, width and height - MUST be initialized there because this information is not - available in the bitstream. */ - - /* open it */ - if (avcodec_open(c, codec) < 0) { - fprintf(stderr, "could not open codec\n"); - exit(1); - } - - /* the codec gives us the frame size, in samples */ - - f = fopen(filename, "rb"); - if (!f) { - fprintf(stderr, "could not open %s\n", filename); - exit(1); - } - - frame = 0; - for(;;) { - avpkt.size = fread(inbuf, 1, INBUF_SIZE, f); - if (avpkt.size == 0) - break; - - /* NOTE1: some codecs are stream based (mpegvideo, mpegaudio) - and this is the only method to use them because you cannot - know the compressed data size before analysing it. - - BUT some other codecs (msmpeg4, mpeg4) are inherently frame - based, so you must call them with all the data for one - frame exactly. You must also initialize 'width' and - 'height' before initializing them. */ - - /* NOTE2: some codecs allow the raw parameters (frame size, - sample rate) to be changed at any frame. We handle this, so - you should also take care of it */ - - /* here, we use a stream based decoder (mpeg1video), so we - feed decoder and see if it could decode a frame */ - avpkt.data = inbuf; - while (avpkt.size > 0) { - len = avcodec_decode_video2(c, picture, &got_picture, &avpkt); - if (len < 0) { - fprintf(stderr, "Error while decoding frame %d\n", frame); - exit(1); - } - if (got_picture) { - printf("saving frame %3d\n", frame); - fflush(stdout); - - /* the picture is allocated by the decoder. no need to - free it */ - snprintf(buf, sizeof(buf), outfilename, frame); - pgm_save(picture->data[0], picture->linesize[0], - c->width, c->height, buf); - frame++; - } - avpkt.size -= len; - avpkt.data += len; - } - } - - /* some codecs, such as MPEG, transmit the I and P frame with a - latency of one frame. You must do the following to have a - chance to get the last frame of the video */ - avpkt.data = NULL; - avpkt.size = 0; - len = avcodec_decode_video2(c, picture, &got_picture, &avpkt); - if (got_picture) { - printf("saving last frame %3d\n", frame); - fflush(stdout); - - /* the picture is allocated by the decoder. no need to - free it */ - snprintf(buf, sizeof(buf), outfilename, frame); - pgm_save(picture->data[0], picture->linesize[0], - c->width, c->height, buf); - frame++; - } - - fclose(f); - - avcodec_close(c); - av_free(c); - av_free(picture); - printf("\n"); -} - -int main(int argc, char **argv) -{ - const char *filename; - - /* must be called before using avcodec lib */ - avcodec_init(); - - /* register all the codecs */ - avcodec_register_all(); - - if (argc <= 1) { - audio_encode_example("/tmp/test.mp2"); - audio_decode_example("/tmp/test.sw", "/tmp/test.mp2"); - - video_encode_example("/tmp/test.mpg"); - filename = "/tmp/test.mpg"; - } else { - filename = argv[1]; - } - - // audio_decode_example("/tmp/test.sw", filename); - video_decode_example("/tmp/test%d.pgm", filename); - - return 0; -} |