*/
#include <stdlib.h>
#include <stdio.h>
+#include <string.h>
#include <math.h>
+#ifndef M_PI
+#define M_PI 3.1415926535897931
+#endif
+
#include "avformat.h"
/* 5 seconds stream duration */
-#define STREAM_DURATION 5.0
-
+#define STREAM_DURATION 5.0
+#define STREAM_FRAME_RATE 25 /* 25 images/s */
+#define STREAM_NB_FRAMES ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
/**************************************************************/
/* audio output */
-float t, tincr;
+float t, tincr, tincr2;
int16_t *samples;
uint8_t *audio_outbuf;
int audio_outbuf_size;
*/
AVStream *add_audio_stream(AVFormatContext *oc, int codec_id)
{
- AVCodec *codec;
AVCodecContext *c;
AVStream *st;
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;
-
- avcodec_get_context_defaults(c);
-
+ 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) {
/* 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);
audio_input_frame_size = c->frame_size;
}
samples = malloc(audio_input_frame_size * 2 * c->channels);
+}
- return st;
+/* prepare a 16 bit dummy audio frame of 'frame_size' samples and
+ 'nb_channels' channels */
+void get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
+{
+ int j, i, v;
+ int16_t *q;
+
+ q = samples;
+ for(j=0;j<frame_size;j++) {
+ v = (int)(sin(t) * 10000);
+ for(i = 0; i < nb_channels; i++)
+ *q++ = v;
+ t += tincr;
+ tincr += tincr2;
+ }
}
void write_audio_frame(AVFormatContext *oc, AVStream *st)
{
- int j, out_size;
+ int out_size;
AVCodecContext *c;
+ AVPacket pkt;
+ av_init_packet(&pkt);
+
+ c = &st->codec;
+ get_audio_frame(samples, audio_input_frame_size, c->channels);
- c = &st->codec;
+ pkt.size= avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples);
- for(j=0;j<audio_input_frame_size;j++) {
- samples[2*j] = (int)(sin(t) * 10000);
- samples[2*j+1] = samples[2*j];
- t += tincr;
- }
-
- out_size = avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples);
+ pkt.pts= c->coded_frame->pts;
+ pkt.flags |= PKT_FLAG_KEY;
+ pkt.stream_index= st->index;
+ pkt.data= audio_outbuf;
/* write the compressed frame in the media file */
- if (av_write_frame(oc, st->index, audio_outbuf, out_size) != 0) {
+ if (av_write_frame(oc, &pkt) != 0) {
fprintf(stderr, "Error while writing audio frame\n");
exit(1);
}
}
+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) {
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;
-
- avcodec_get_context_defaults(c);
-
+ c->codec_id = codec_id;
c->codec_type = CODEC_TYPE_VIDEO;
/* put sample parameters */
c->width = 352;
c->height = 288;
/* frames per second */
- c->frame_rate = 25;
- c->frame_rate_base= 1;
- c->gop_size = 12; /* emit one intra frame every twelve frames */
+ c->frame_rate = STREAM_FRAME_RATE;
+ c->frame_rate_base = 1;
+ c->gop_size = 12; /* emit one intra frame every twelve frames at most */
+ if (c->codec_id == CODEC_ID_MPEG2VIDEO) {
+ /* just for testing, we also add B frames */
+ c->max_b_frames = 2;
+ }
+ if (c->codec_id == CODEC_ID_MPEG1VIDEO){
+ /* needed to avoid using macroblocks in which some coeffs overflow
+ this doesnt happen with normal video, it just happens here as the
+ motion of the chroma plane doesnt match the luma plane */
+ c->mb_decision=2;
+ }
+ // some formats want stream headers to be seperate
+ if(!strcmp(oc->oformat->name, "mp4") || !strcmp(oc->oformat->name, "mov") || !strcmp(oc->oformat->name, "3gp"))
+ c->flags |= CODEC_FLAG_GLOBAL_HEADER;
+
+ return st;
+}
- /* open it */
+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;
+ AVFrame *picture_ptr;
+
+ c = &st->codec;
+
+ if (frame_count >= STREAM_NB_FRAMES) {
+ /* no more frame to compress. The codec has a latency of a few
+ frames if using B frames, so we get the last frames by
+ passing a NULL picture */
+ picture_ptr = NULL;
+ } else {
+ 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);
+ }
+ picture_ptr = picture;
+ }
- /* write the compressed frame in the media file */
- if (av_write_frame(oc, st->index, video_outbuf, out_size) != 0) {
+
+ if (oc->oformat->flags & AVFMT_RAWPICTURE) {
+ /* raw video case. The API will change slightly in the near
+ futur for that */
+ AVPacket pkt;
+ av_init_packet(&pkt);
+
+ pkt.flags |= PKT_FLAG_KEY;
+ pkt.stream_index= st->index;
+ pkt.data= (uint8_t *)picture_ptr;
+ pkt.size= sizeof(AVPicture);
+
+ ret = av_write_frame(oc, &pkt);
+ } else {
+ /* encode the image */
+ out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture_ptr);
+ /* if zero size, it means the image was buffered */
+ if (out_size != 0) {
+ AVPacket pkt;
+ av_init_packet(&pkt);
+
+ pkt.pts= c->coded_frame->pts;
+ if(c->coded_frame->key_frame)
+ pkt.flags |= PKT_FLAG_KEY;
+ pkt.stream_index= st->index;
+ pkt.data= video_outbuf;
+ pkt.size= out_size;
+
+ /* write the compressed frame in the media file */
+ ret = av_write_frame(oc, &pkt);
+ } else {
+ ret = 0;
+ }
+ }
+ 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);
}
/**************************************************************/
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);
}
}
/* allocate the output media context */
- oc = av_mallocz(sizeof(AVFormatContext));
+ oc = av_alloc_format_context();
if (!oc) {
fprintf(stderr, "Memory error\n");
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 */
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) {
}
}
- /* 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);
for(;;) {
/* compute current audio and video time */
if (audio_st)
- audio_pts = (double)audio_st->pts.val * oc->pts_num / oc->pts_den;
+ audio_pts = (double)audio_st->pts.val * audio_st->time_base.num / audio_st->time_base.den;
else
audio_pts = 0.0;
if (video_st)
- video_pts = (double)video_st->pts.val * oc->pts_num / oc->pts_den;
+ video_pts = (double)video_st->pts.val * video_st->time_base.num / video_st->time_base.den;
else
video_pts = 0.0;
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);
}
/* 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);