diff options
| -rw-r--r-- | output_example.c | 251 |
1 files changed, 183 insertions, 68 deletions
diff --git a/output_example.c b/output_example.c index faaaca9..0e06b0c 100644 --- a/output_example.c +++ b/output_example.c @@ -35,7 +35,7 @@ /**************************************************************/ /* audio output */ -float t, tincr; +float t, tincr, tincr2; int16_t *samples; uint8_t *audio_outbuf; int audio_outbuf_size; @@ -46,7 +46,6 @@ int audio_input_frame_size; */ AVStream *add_audio_stream(AVFormatContext *oc, int codec_id) { - AVCodec *codec; AVCodecContext *c; AVStream *st; @@ -56,19 +55,30 @@ AVStream *add_audio_stream(AVFormatContext *oc, int codec_id) exit(1); } - /* find the MP2 encoder */ - codec = avcodec_find_encoder(codec_id); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } c = &st->codec; + c->codec_id = codec_id; c->codec_type = CODEC_TYPE_AUDIO; /* put sample parameters */ c->bit_rate = 64000; c->sample_rate = 44100; c->channels = 2; + return st; +} + +void open_audio(AVFormatContext *oc, AVStream *st) +{ + AVCodecContext *c; + AVCodec *codec; + + c = &st->codec; + + /* find the audio encoder */ + codec = avcodec_find_encoder(c->codec_id); + if (!codec) { + fprintf(stderr, "codec not found\n"); + exit(1); + } /* open it */ if (avcodec_open(c, codec) < 0) { @@ -78,7 +88,9 @@ AVStream *add_audio_stream(AVFormatContext *oc, int codec_id) /* init signal generator */ t = 0; - tincr = 2 * M_PI * 440.0 / c->sample_rate; + tincr = 2 * M_PI * 110.0 / c->sample_rate; + /* increment frequency by 110 Hz per second */ + tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate; audio_outbuf_size = 10000; audio_outbuf = malloc(audio_outbuf_size); @@ -101,8 +113,6 @@ AVStream *add_audio_stream(AVFormatContext *oc, int codec_id) audio_input_frame_size = c->frame_size; } samples = malloc(audio_input_frame_size * 2 * c->channels); - - return st; } void write_audio_frame(AVFormatContext *oc, AVStream *st) @@ -117,6 +127,7 @@ void write_audio_frame(AVFormatContext *oc, AVStream *st) samples[2*j] = (int)(sin(t) * 10000); samples[2*j+1] = samples[2*j]; t += tincr; + tincr += tincr2; } out_size = avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples); @@ -128,21 +139,26 @@ void write_audio_frame(AVFormatContext *oc, AVStream *st) } } +void close_audio(AVFormatContext *oc, AVStream *st) +{ + avcodec_close(&st->codec); + + av_free(samples); + av_free(audio_outbuf); +} + /**************************************************************/ /* video output */ -AVFrame *picture; +AVFrame *picture, *tmp_picture; uint8_t *video_outbuf; int frame_count, video_outbuf_size; /* add a video output stream */ AVStream *add_video_stream(AVFormatContext *oc, int codec_id) { - AVCodec *codec; AVCodecContext *c; AVStream *st; - uint8_t *picture_buf; - int size; st = av_new_stream(oc, 0); if (!st) { @@ -150,14 +166,8 @@ AVStream *add_video_stream(AVFormatContext *oc, int codec_id) exit(1); } - /* find the mpeg1 video encoder */ - codec = avcodec_find_encoder(codec_id); - if (!codec) { - fprintf(stderr, "codec not found\n"); - exit(1); - } - c = &st->codec; + c->codec_id = codec_id; c->codec_type = CODEC_TYPE_VIDEO; /* put sample parameters */ @@ -170,62 +180,148 @@ AVStream *add_video_stream(AVFormatContext *oc, int codec_id) c->frame_rate_base= 1; c->gop_size = 12; /* emit one intra frame every twelve frames */ - /* open it */ + return st; +} + +AVFrame *alloc_picture(int pix_fmt, int width, int height) +{ + AVFrame *picture; + uint8_t *picture_buf; + int size; + + picture = avcodec_alloc_frame(); + if (!picture) + return NULL; + size = avpicture_get_size(pix_fmt, width, height); + picture_buf = malloc(size); + if (!picture_buf) { + av_free(picture); + return NULL; + } + avpicture_fill((AVPicture *)picture, picture_buf, + pix_fmt, width, height); + return picture; +} + +void open_video(AVFormatContext *oc, AVStream *st) +{ + AVCodec *codec; + AVCodecContext *c; + + c = &st->codec; + + /* find the video encoder */ + codec = avcodec_find_encoder(c->codec_id); + if (!codec) { + fprintf(stderr, "codec not found\n"); + exit(1); + } + + /* open the codec */ if (avcodec_open(c, codec) < 0) { fprintf(stderr, "could not open codec\n"); exit(1); } - /* alloc various buffers */ - picture= avcodec_alloc_frame(); - video_outbuf_size = 100000; - video_outbuf = malloc(video_outbuf_size); + video_outbuf = NULL; + if (!(oc->oformat->flags & AVFMT_RAWPICTURE)) { + /* allocate output buffer */ + /* XXX: API change will be done */ + video_outbuf_size = 200000; + video_outbuf = malloc(video_outbuf_size); + } - size = c->width * c->height; - picture_buf = malloc((size * 3) / 2); /* size for YUV 420 */ - - picture->data[0] = picture_buf; - picture->data[1] = picture->data[0] + size; - picture->data[2] = picture->data[1] + size / 4; - picture->linesize[0] = c->width; - picture->linesize[1] = c->width / 2; - picture->linesize[2] = c->width / 2; + /* allocate the encoded raw picture */ + picture = alloc_picture(c->pix_fmt, c->width, c->height); + if (!picture) { + fprintf(stderr, "Could not allocate picture\n"); + exit(1); + } - return st; -} + /* if the output format is not YUV420P, then a temporary YUV420P + picture is needed too. It is then converted to the required + output format */ + tmp_picture = NULL; + if (c->pix_fmt != PIX_FMT_YUV420P) { + tmp_picture = alloc_picture(PIX_FMT_YUV420P, c->width, c->height); + if (!tmp_picture) { + fprintf(stderr, "Could not allocate temporary picture\n"); + exit(1); + } + } +} -void write_video_frame(AVFormatContext *oc, AVStream *st) +/* prepare a dummy image */ +void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height) { - int x, y, i, out_size; - AVCodecContext *c; + int x, y, i; + + i = frame_index; - c = &st->codec; - - /* prepare a dummy image */ /* Y */ - i = frame_count++; - 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; + for(y=0;y<height;y++) { + for(x=0;x<width;x++) { + pict->data[0][y * pict->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; + for(y=0;y<height/2;y++) { + for(x=0;x<width/2;x++) { + pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2; + pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5; } } +} - /* encode the image */ - out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture); +void write_video_frame(AVFormatContext *oc, AVStream *st) +{ + int out_size, ret; + AVCodecContext *c; - /* write the compressed frame in the media file */ - if (av_write_frame(oc, st->index, video_outbuf, out_size) != 0) { + c = &st->codec; + + if (c->pix_fmt != PIX_FMT_YUV420P) { + /* as we only generate a YUV420P picture, we must convert it + to the codec pixel format if needed */ + fill_yuv_image(tmp_picture, frame_count, c->width, c->height); + img_convert((AVPicture *)picture, c->pix_fmt, + (AVPicture *)tmp_picture, PIX_FMT_YUV420P, + c->width, c->height); + } else { + fill_yuv_image(picture, frame_count, c->width, c->height); + } + + + if (oc->oformat->flags & AVFMT_RAWPICTURE) { + /* raw video case. The API will change slightly in the near + futur for that */ + ret = av_write_frame(oc, st->index, + (uint8_t *)picture, sizeof(AVPicture)); + } else { + /* encode the image */ + out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture); + + /* write the compressed frame in the media file */ + ret = av_write_frame(oc, st->index, video_outbuf, out_size); + } + if (ret != 0) { fprintf(stderr, "Error while writing video frame\n"); exit(1); } + frame_count++; +} + +void close_video(AVFormatContext *oc, AVStream *st) +{ + avcodec_close(&st->codec); + av_free(picture->data[0]); + av_free(picture); + if (tmp_picture) { + av_free(tmp_picture->data[0]); + av_free(tmp_picture); + } + av_free(video_outbuf); } /**************************************************************/ @@ -236,16 +332,18 @@ int main(int argc, char **argv) const char *filename; AVOutputFormat *fmt; AVFormatContext *oc; - AVStream *st, *audio_st, *video_st; - int i; + AVStream *audio_st, *video_st; double audio_pts, video_pts; - + int i; + /* initialize libavcodec, and register all codecs and formats */ av_register_all(); if (argc != 2) { printf("usage: %s output_file\n" - "API example program for to output media file with libavformat\n" + "API example program to output a media file with libavformat.\n" + "The output format is automatically guessed according to the file extension.\n" + "Raw images can also be output by using '%%d' in the filename\n" "\n", argv[0]); exit(1); } @@ -271,6 +369,7 @@ int main(int argc, char **argv) exit(1); } oc->oformat = fmt; + snprintf(oc->filename, sizeof(oc->filename), "%s", filename); /* add the audio and video streams using the default format codecs and initialize the codecs */ @@ -283,8 +382,22 @@ int main(int argc, char **argv) audio_st = add_audio_stream(oc, fmt->audio_codec); } + /* set the output parameters (must be done even if no + parameters). */ + if (av_set_parameters(oc, NULL) < 0) { + fprintf(stderr, "Invalid output format parameters\n"); + exit(1); + } + dump_format(oc, 0, filename, 1); + /* 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_st); + if (audio_st) + open_audio(oc, audio_st); + /* open the output file, if needed */ if (!(fmt->flags & AVFMT_NOFILE)) { if (url_fopen(&oc->pb, filename, URL_WRONLY) < 0) { @@ -293,9 +406,6 @@ int main(int argc, char **argv) } } - /* set the output parameters (must be done even if no parameters) */ - av_set_parameters(oc, NULL); - /* write the stream header, if any */ av_write_header(oc); @@ -316,7 +426,7 @@ int main(int argc, char **argv) break; /* write interleaved audio and video frames */ - if (!video_st || (video_st && audio_pts < video_pts)) { + if (!video_st || (video_st && audio_st && audio_pts < video_pts)) { write_audio_frame(oc, audio_st); } else { write_video_frame(oc, video_st); @@ -324,14 +434,19 @@ int main(int argc, char **argv) } /* close each codec */ - for(i = 0;i < oc->nb_streams; i++) { - st = oc->streams[i]; - avcodec_close(&st->codec); - } + if (video_st) + close_video(oc, video_st); + if (audio_st) + close_audio(oc, audio_st); /* write the trailer, if any */ av_write_trailer(oc); + /* free the streams */ + for(i = 0; i < oc->nb_streams; i++) { + av_freep(&oc->streams[i]); + } + if (!(fmt->flags & AVFMT_NOFILE)) { /* close the output file */ url_fclose(&oc->pb); |
