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https://git.videolan.org/git/ffmpeg.git
synced 2024-09-09 17:20:21 +02:00
output example: use a struct to bundle the video stream variables together
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38d044429d
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294daf71a7
@ -46,6 +46,14 @@
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static int sws_flags = SWS_BICUBIC;
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// a wrapper around a single output AVStream
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typedef struct OutputStream {
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AVStream *st;
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AVFrame *frame;
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AVFrame *tmp_frame;
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} OutputStream;
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/**************************************************************/
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/* audio output */
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@ -176,14 +184,13 @@ static void close_audio(AVFormatContext *oc, AVStream *st)
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/**************************************************************/
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/* video output */
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static AVFrame *picture, *tmp_picture;
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static int frame_count;
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/* Add a video output stream. */
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static AVStream *add_video_stream(AVFormatContext *oc, enum AVCodecID codec_id)
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static void add_video_stream(OutputStream *ost, AVFormatContext *oc,
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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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AVCodec *codec;
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/* find the video encoder */
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@ -193,13 +200,13 @@ static AVStream *add_video_stream(AVFormatContext *oc, enum AVCodecID 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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ost->st = avformat_new_stream(oc, codec);
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if (!ost->st) {
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fprintf(stderr, "Could not alloc stream\n");
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exit(1);
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}
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c = st->codec;
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c = ost->st->codec;
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/* Put sample parameters. */
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c->bit_rate = 400000;
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@ -227,8 +234,6 @@ static AVStream *add_video_stream(AVFormatContext *oc, enum AVCodecID codec_id)
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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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static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
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@ -254,11 +259,11 @@ static AVFrame *alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
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return picture;
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}
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static void open_video(AVFormatContext *oc, AVStream *st)
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static void open_video(AVFormatContext *oc, OutputStream *ost)
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{
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AVCodecContext *c;
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c = st->codec;
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c = ost->st->codec;
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/* open the codec */
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if (avcodec_open2(c, NULL, NULL) < 0) {
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@ -267,8 +272,8 @@ static void open_video(AVFormatContext *oc, AVStream *st)
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}
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/* Allocate the encoded raw picture. */
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picture = alloc_picture(c->pix_fmt, c->width, c->height);
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if (!picture) {
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ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
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if (!ost->frame) {
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fprintf(stderr, "Could not allocate picture\n");
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exit(1);
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}
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@ -276,10 +281,10 @@ static void open_video(AVFormatContext *oc, AVStream *st)
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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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tmp_picture = NULL;
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ost->tmp_frame = NULL;
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if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
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tmp_picture = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
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if (!tmp_picture) {
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ost->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
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if (!ost->tmp_frame) {
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fprintf(stderr, "Could not allocate temporary picture\n");
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exit(1);
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}
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@ -316,13 +321,13 @@ static void fill_yuv_image(AVFrame *pict, int frame_index,
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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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static void write_video_frame(AVFormatContext *oc, OutputStream *ost)
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{
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int ret;
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AVCodecContext *c;
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static struct SwsContext *img_convert_ctx;
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c = st->codec;
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c = ost->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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@ -344,11 +349,11 @@ static void write_video_frame(AVFormatContext *oc, AVStream *st)
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exit(1);
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}
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}
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fill_yuv_image(tmp_picture, frame_count, c->width, c->height);
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sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize,
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0, c->height, picture->data, picture->linesize);
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fill_yuv_image(ost->tmp_frame, frame_count, c->width, c->height);
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sws_scale(img_convert_ctx, ost->tmp_frame->data, ost->tmp_frame->linesize,
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0, c->height, ost->frame->data, ost->frame->linesize);
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} else {
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fill_yuv_image(picture, frame_count, c->width, c->height);
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fill_yuv_image(ost->frame, frame_count, c->width, c->height);
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}
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}
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@ -359,8 +364,8 @@ static void write_video_frame(AVFormatContext *oc, AVStream *st)
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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 = (uint8_t *)picture;
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pkt.stream_index = ost->st->index;
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pkt.data = (uint8_t *)ost->frame;
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pkt.size = sizeof(AVPicture);
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ret = av_interleaved_write_frame(oc, &pkt);
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@ -370,11 +375,11 @@ static void write_video_frame(AVFormatContext *oc, AVStream *st)
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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, picture, &got_packet);
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ret = avcodec_encode_video2(c, &pkt, ost->frame, &got_packet);
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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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av_packet_rescale_ts(&pkt, c->time_base, st->time_base);
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pkt.stream_index = st->index;
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av_packet_rescale_ts(&pkt, c->time_base, ost->st->time_base);
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pkt.stream_index = ost->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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@ -389,11 +394,11 @@ static void write_video_frame(AVFormatContext *oc, AVStream *st)
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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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static void close_video(AVFormatContext *oc, OutputStream *ost)
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{
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avcodec_close(st->codec);
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av_frame_free(&picture);
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av_frame_free(&tmp_picture);
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avcodec_close(ost->st->codec);
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av_frame_free(&ost->frame);
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av_frame_free(&ost->tmp_frame);
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}
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/**************************************************************/
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@ -401,11 +406,13 @@ static void close_video(AVFormatContext *oc, AVStream *st)
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int main(int argc, char **argv)
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{
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OutputStream video_st;
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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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AVStream *audio_st;
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double audio_pts, video_pts;
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int have_video = 0;
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int i;
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/* Initialize libavcodec, and register all codecs and formats. */
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@ -444,10 +451,10 @@ int main(int argc, char **argv)
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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) {
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video_st = add_video_stream(oc, fmt->video_codec);
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add_video_stream(&video_st, oc, fmt->video_codec);
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have_video = 1;
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}
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if (fmt->audio_codec != AV_CODEC_ID_NONE) {
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audio_st = add_audio_stream(oc, fmt->audio_codec);
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@ -455,8 +462,8 @@ int main(int argc, char **argv)
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/* Now that all the parameters are set, we can open the audio and
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* video codecs and allocate the necessary encode buffers. */
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if (video_st)
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open_video(oc, video_st);
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if (have_video)
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open_video(oc, &video_st);
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if (audio_st)
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open_audio(oc, audio_st);
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@ -480,21 +487,21 @@ int main(int argc, char **argv)
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else
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audio_pts = 0.0;
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if (video_st)
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video_pts = (double)video_st->pts.val * video_st->time_base.num /
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video_st->time_base.den;
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if (have_video)
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video_pts = (double)video_st.st->pts.val * video_st.st->time_base.num /
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video_st.st->time_base.den;
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else
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video_pts = 0.0;
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if ((!audio_st || audio_pts >= STREAM_DURATION) &&
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(!video_st || video_pts >= STREAM_DURATION))
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(!have_video || video_pts >= STREAM_DURATION))
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break;
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/* write interleaved audio and video frames */
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if (!video_st || (video_st && audio_st && audio_pts < video_pts)) {
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if (!have_video || (have_video && audio_st && audio_pts < video_pts)) {
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write_audio_frame(oc, audio_st);
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} else {
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write_video_frame(oc, video_st);
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write_video_frame(oc, &video_st);
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}
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}
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@ -505,8 +512,8 @@ int main(int argc, char **argv)
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av_write_trailer(oc);
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/* Close each codec. */
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if (video_st)
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close_video(oc, video_st);
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if (have_video)
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close_video(oc, &video_st);
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if (audio_st)
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close_audio(oc, audio_st);
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