yading@10: /*
yading@10:  * Copyright (c) 2003 Fabrice Bellard
yading@10:  *
yading@10:  * Permission is hereby granted, free of charge, to any person obtaining a copy
yading@10:  * of this software and associated documentation files (the "Software"), to deal
yading@10:  * in the Software without restriction, including without limitation the rights
yading@10:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
yading@10:  * copies of the Software, and to permit persons to whom the Software is
yading@10:  * furnished to do so, subject to the following conditions:
yading@10:  *
yading@10:  * The above copyright notice and this permission notice shall be included in
yading@10:  * all copies or substantial portions of the Software.
yading@10:  *
yading@10:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
yading@10:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
yading@10:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
yading@10:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
yading@10:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
yading@10:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
yading@10:  * THE SOFTWARE.
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * libavformat API example.
yading@10:  *
yading@10:  * Output a media file in any supported libavformat format.
yading@10:  * The default codecs are used.
yading@10:  * @example doc/examples/muxing.c
yading@10:  */
yading@10: 
yading@10: #include <stdlib.h>
yading@10: #include <stdio.h>
yading@10: #include <string.h>
yading@10: #include <math.h>
yading@10: 
yading@10: #include <libavutil/mathematics.h>
yading@10: #include <libavformat/avformat.h>
yading@10: #include <libswscale/swscale.h>
yading@10: 
yading@10: /* 5 seconds stream duration */
yading@10: #define STREAM_DURATION   200.0
yading@10: #define STREAM_FRAME_RATE 25 /* 25 images/s */
yading@10: #define STREAM_NB_FRAMES  ((int)(STREAM_DURATION * STREAM_FRAME_RATE))
yading@10: #define STREAM_PIX_FMT    AV_PIX_FMT_YUV420P /* default pix_fmt */
yading@10: 
yading@10: static int sws_flags = SWS_BICUBIC;
yading@10: 
yading@10: /**************************************************************/
yading@10: /* audio output */
yading@10: 
yading@10: static float t, tincr, tincr2;
yading@10: static int16_t *samples;
yading@10: static int audio_input_frame_size;
yading@10: 
yading@10: /* Add an output stream. */
yading@10: static AVStream *add_stream(AVFormatContext *oc, AVCodec **codec,
yading@10:                             enum AVCodecID codec_id)
yading@10: {
yading@10:     AVCodecContext *c;
yading@10:     AVStream *st;
yading@10: 
yading@10:     /* find the encoder */
yading@10:     *codec = avcodec_find_encoder(codec_id);
yading@10:     if (!(*codec)) {
yading@10:         fprintf(stderr, "Could not find encoder for '%s'\n",
yading@10:                 avcodec_get_name(codec_id));
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     st = avformat_new_stream(oc, *codec);
yading@10:     if (!st) {
yading@10:         fprintf(stderr, "Could not allocate stream\n");
yading@10:         exit(1);
yading@10:     }
yading@10:     st->id = oc->nb_streams-1;
yading@10:     c = st->codec;
yading@10: 
yading@10:     switch ((*codec)->type) {
yading@10:     case AVMEDIA_TYPE_AUDIO:
yading@10:         st->id = 1;
yading@10:         c->sample_fmt  = AV_SAMPLE_FMT_S16;
yading@10:         c->bit_rate    = 64000;
yading@10:         c->sample_rate = 44100;
yading@10:         c->channels    = 2;
yading@10:         break;
yading@10: 
yading@10:     case AVMEDIA_TYPE_VIDEO:
yading@10:         c->codec_id = codec_id;
yading@10: 
yading@10:         c->bit_rate = 400000;
yading@10:         /* Resolution must be a multiple of two. */
yading@10:         c->width    = 352;
yading@10:         c->height   = 288;
yading@10:         /* timebase: This is the fundamental unit of time (in seconds) in terms
yading@10:          * of which frame timestamps are represented. For fixed-fps content,
yading@10:          * timebase should be 1/framerate and timestamp increments should be
yading@10:          * identical to 1. */
yading@10:         c->time_base.den = STREAM_FRAME_RATE;
yading@10:         c->time_base.num = 1;
yading@10:         c->gop_size      = 12; /* emit one intra frame every twelve frames at most */
yading@10:         c->pix_fmt       = STREAM_PIX_FMT;
yading@10:         if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
yading@10:             /* just for testing, we also add B frames */
yading@10:             c->max_b_frames = 2;
yading@10:         }
yading@10:         if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
yading@10:             /* Needed to avoid using macroblocks in which some coeffs overflow.
yading@10:              * This does not happen with normal video, it just happens here as
yading@10:              * the motion of the chroma plane does not match the luma plane. */
yading@10:             c->mb_decision = 2;
yading@10:         }
yading@10:     break;
yading@10: 
yading@10:     default:
yading@10:         break;
yading@10:     }
yading@10: 
yading@10:     /* Some formats want stream headers to be separate. */
yading@10:     if (oc->oformat->flags & AVFMT_GLOBALHEADER)
yading@10:         c->flags |= CODEC_FLAG_GLOBAL_HEADER;
yading@10: 
yading@10:     return st;
yading@10: }
yading@10: 
yading@10: /**************************************************************/
yading@10: /* audio output */
yading@10: 
yading@10: static float t, tincr, tincr2;
yading@10: static int16_t *samples;
yading@10: static int audio_input_frame_size;
yading@10: 
yading@10: static void open_audio(AVFormatContext *oc, AVCodec *codec, AVStream *st)
yading@10: {
yading@10:     AVCodecContext *c;
yading@10:     int ret;
yading@10: 
yading@10:     c = st->codec;
yading@10: 
yading@10:     /* open it */
yading@10:     ret = avcodec_open2(c, codec, NULL);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Could not open audio codec: %s\n", av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     /* init signal generator */
yading@10:     t     = 0;
yading@10:     tincr = 2 * M_PI * 110.0 / c->sample_rate;
yading@10:     /* increment frequency by 110 Hz per second */
yading@10:     tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
yading@10: 
yading@10:     if (c->codec->capabilities & CODEC_CAP_VARIABLE_FRAME_SIZE)
yading@10:         audio_input_frame_size = 10000;
yading@10:     else
yading@10:         audio_input_frame_size = c->frame_size;
yading@10:     samples = av_malloc(audio_input_frame_size *
yading@10:                         av_get_bytes_per_sample(c->sample_fmt) *
yading@10:                         c->channels);
yading@10:     if (!samples) {
yading@10:         fprintf(stderr, "Could not allocate audio samples buffer\n");
yading@10:         exit(1);
yading@10:     }
yading@10: }
yading@10: 
yading@10: /* Prepare a 16 bit dummy audio frame of 'frame_size' samples and
yading@10:  * 'nb_channels' channels. */
yading@10: static void get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
yading@10: {
yading@10:     int j, i, v;
yading@10:     int16_t *q;
yading@10: 
yading@10:     q = samples;
yading@10:     for (j = 0; j < frame_size; j++) {
yading@10:         v = (int)(sin(t) * 10000);
yading@10:         for (i = 0; i < nb_channels; i++)
yading@10:             *q++ = v;
yading@10:         t     += tincr;
yading@10:         tincr += tincr2;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static void write_audio_frame(AVFormatContext *oc, AVStream *st)
yading@10: {
yading@10:     AVCodecContext *c;
yading@10:     AVPacket pkt = { 0 }; // data and size must be 0;
yading@10:     AVFrame *frame = avcodec_alloc_frame();
yading@10:     int got_packet, ret;
yading@10: 
yading@10:     av_init_packet(&pkt);
yading@10:     c = st->codec;
yading@10: 
yading@10:     get_audio_frame(samples, audio_input_frame_size, c->channels);
yading@10:     frame->nb_samples = audio_input_frame_size;
yading@10:     avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt,
yading@10:                              (uint8_t *)samples,
yading@10:                              audio_input_frame_size *
yading@10:                              av_get_bytes_per_sample(c->sample_fmt) *
yading@10:                              c->channels, 1);
yading@10: 
yading@10:     ret = avcodec_encode_audio2(c, &pkt, frame, &got_packet);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Error encoding audio frame: %s\n", av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     if (!got_packet)
yading@10:         return;
yading@10: 
yading@10:     pkt.stream_index = st->index;
yading@10: 
yading@10:     /* Write the compressed frame to the media file. */
yading@10:     ret = av_interleaved_write_frame(oc, &pkt);
yading@10:     if (ret != 0) {
yading@10:         fprintf(stderr, "Error while writing audio frame: %s\n",
yading@10:                 av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10:     avcodec_free_frame(&frame);
yading@10: }
yading@10: 
yading@10: static void close_audio(AVFormatContext *oc, AVStream *st)
yading@10: {
yading@10:     avcodec_close(st->codec);
yading@10: 
yading@10:     av_free(samples);
yading@10: }
yading@10: 
yading@10: /**************************************************************/
yading@10: /* video output */
yading@10: 
yading@10: static AVFrame *frame;
yading@10: static AVPicture src_picture, dst_picture;
yading@10: static int frame_count;
yading@10: 
yading@10: static void open_video(AVFormatContext *oc, AVCodec *codec, AVStream *st)
yading@10: {
yading@10:     int ret;
yading@10:     AVCodecContext *c = st->codec;
yading@10: 
yading@10:     /* open the codec */
yading@10:     ret = avcodec_open2(c, codec, NULL);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     /* allocate and init a re-usable frame */
yading@10:     frame = avcodec_alloc_frame();
yading@10:     if (!frame) {
yading@10:         fprintf(stderr, "Could not allocate video frame\n");
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     /* Allocate the encoded raw picture. */
yading@10:     ret = avpicture_alloc(&dst_picture, c->pix_fmt, c->width, c->height);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Could not allocate picture: %s\n", av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10: 
yading@10:     /* If the output format is not YUV420P, then a temporary YUV420P
yading@10:      * picture is needed too. It is then converted to the required
yading@10:      * output format. */
yading@10:     if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
yading@10:         ret = avpicture_alloc(&src_picture, AV_PIX_FMT_YUV420P, c->width, c->height);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Could not allocate temporary picture: %s\n",
yading@10:                     av_err2str(ret));
yading@10:             exit(1);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     /* copy data and linesize picture pointers to frame */
yading@10:     *((AVPicture *)frame) = dst_picture;
yading@10: }
yading@10: 
yading@10: /* Prepare a dummy image. */
yading@10: static void fill_yuv_image(AVPicture *pict, int frame_index,
yading@10:                            int width, int height)
yading@10: {
yading@10:     int x, y, i;
yading@10: 
yading@10:     i = frame_index;
yading@10: 
yading@10:     /* Y */
yading@10:     for (y = 0; y < height; y++)
yading@10:         for (x = 0; x < width; x++)
yading@10:             pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
yading@10: 
yading@10:     /* Cb and Cr */
yading@10:     for (y = 0; y < height / 2; y++) {
yading@10:         for (x = 0; x < width / 2; x++) {
yading@10:             pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
yading@10:             pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
yading@10:         }
yading@10:     }
yading@10: }
yading@10: 
yading@10: static void write_video_frame(AVFormatContext *oc, AVStream *st)
yading@10: {
yading@10:     int ret;
yading@10:     static struct SwsContext *sws_ctx;
yading@10:     AVCodecContext *c = st->codec;
yading@10: 
yading@10:     if (frame_count >= STREAM_NB_FRAMES) {
yading@10:         /* No more frames to compress. The codec has a latency of a few
yading@10:          * frames if using B-frames, so we get the last frames by
yading@10:          * passing the same picture again. */
yading@10:     } else {
yading@10:         if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
yading@10:             /* as we only generate a YUV420P picture, we must convert it
yading@10:              * to the codec pixel format if needed */
yading@10:             if (!sws_ctx) {
yading@10:                 sws_ctx = sws_getContext(c->width, c->height, AV_PIX_FMT_YUV420P,
yading@10:                                          c->width, c->height, c->pix_fmt,
yading@10:                                          sws_flags, NULL, NULL, NULL);
yading@10:                 if (!sws_ctx) {
yading@10:                     fprintf(stderr,
yading@10:                             "Could not initialize the conversion context\n");
yading@10:                     exit(1);
yading@10:                 }
yading@10:             }
yading@10:             fill_yuv_image(&src_picture, frame_count, c->width, c->height);
yading@10:             sws_scale(sws_ctx,
yading@10:                       (const uint8_t * const *)src_picture.data, src_picture.linesize,
yading@10:                       0, c->height, dst_picture.data, dst_picture.linesize);
yading@10:         } else {
yading@10:             fill_yuv_image(&dst_picture, frame_count, c->width, c->height);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if (oc->oformat->flags & AVFMT_RAWPICTURE) {
yading@10:         /* Raw video case - directly store the picture in the packet */
yading@10:         AVPacket pkt;
yading@10:         av_init_packet(&pkt);
yading@10: 
yading@10:         pkt.flags        |= AV_PKT_FLAG_KEY;
yading@10:         pkt.stream_index  = st->index;
yading@10:         pkt.data          = dst_picture.data[0];
yading@10:         pkt.size          = sizeof(AVPicture);
yading@10: 
yading@10:         ret = av_interleaved_write_frame(oc, &pkt);
yading@10:     } else {
yading@10:         AVPacket pkt = { 0 };
yading@10:         int got_packet;
yading@10:         av_init_packet(&pkt);
yading@10: 
yading@10:         /* encode the image */
yading@10:         ret = avcodec_encode_video2(c, &pkt, frame, &got_packet);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Error encoding video frame: %s\n", av_err2str(ret));
yading@10:             exit(1);
yading@10:         }
yading@10:         /* If size is zero, it means the image was buffered. */
yading@10: 
yading@10:         if (!ret && got_packet && pkt.size) {
yading@10:             pkt.stream_index = st->index;
yading@10: 
yading@10:             /* Write the compressed frame to the media file. */
yading@10:             ret = av_interleaved_write_frame(oc, &pkt);
yading@10:         } else {
yading@10:             ret = 0;
yading@10:         }
yading@10:     }
yading@10:     if (ret != 0) {
yading@10:         fprintf(stderr, "Error while writing video frame: %s\n", av_err2str(ret));
yading@10:         exit(1);
yading@10:     }
yading@10:     frame_count++;
yading@10: }
yading@10: 
yading@10: static void close_video(AVFormatContext *oc, AVStream *st)
yading@10: {
yading@10:     avcodec_close(st->codec);
yading@10:     av_free(src_picture.data[0]);
yading@10:     av_free(dst_picture.data[0]);
yading@10:     av_free(frame);
yading@10: }
yading@10: 
yading@10: /**************************************************************/
yading@10: /* media file output */
yading@10: 
yading@10: int main(int argc, char **argv)
yading@10: {
yading@10:     const char *filename;
yading@10:     AVOutputFormat *fmt;
yading@10:     AVFormatContext *oc;
yading@10:     AVStream *audio_st, *video_st;
yading@10:     AVCodec *audio_codec, *video_codec;
yading@10:     double audio_pts, video_pts;
yading@10:     int ret;
yading@10: 
yading@10:     /* Initialize libavcodec, and register all codecs and formats. */
yading@10:     av_register_all();
yading@10: 
yading@10:     if (argc != 2) {
yading@10:         printf("usage: %s output_file\n"
yading@10:                "API example program to output a media file with libavformat.\n"
yading@10:                "This program generates a synthetic audio and video stream, encodes and\n"
yading@10:                "muxes them into a file named output_file.\n"
yading@10:                "The output format is automatically guessed according to the file extension.\n"
yading@10:                "Raw images can also be output by using '%%d' in the filename.\n"
yading@10:                "\n", argv[0]);
yading@10:         return 1;
yading@10:     }
yading@10: 
yading@10:     filename = argv[1];
yading@10: 
yading@10:     /* allocate the output media context */
yading@10:     avformat_alloc_output_context2(&oc, NULL, NULL, filename);
yading@10:     if (!oc) {
yading@10:         printf("Could not deduce output format from file extension: using MPEG.\n");
yading@10:         avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
yading@10:     }
yading@10:     if (!oc) {
yading@10:         return 1;
yading@10:     }
yading@10:     fmt = oc->oformat;
yading@10: 
yading@10:     /* Add the audio and video streams using the default format codecs
yading@10:      * and initialize the codecs. */
yading@10:     video_st = NULL;
yading@10:     audio_st = NULL;
yading@10: 
yading@10:     if (fmt->video_codec != AV_CODEC_ID_NONE) {
yading@10:         video_st = add_stream(oc, &video_codec, fmt->video_codec);
yading@10:     }
yading@10:     if (fmt->audio_codec != AV_CODEC_ID_NONE) {
yading@10:         audio_st = add_stream(oc, &audio_codec, fmt->audio_codec);
yading@10:     }
yading@10: 
yading@10:     /* Now that all the parameters are set, we can open the audio and
yading@10:      * video codecs and allocate the necessary encode buffers. */
yading@10:     if (video_st)
yading@10:         open_video(oc, video_codec, video_st);
yading@10:     if (audio_st)
yading@10:         open_audio(oc, audio_codec, audio_st);
yading@10: 
yading@10:     av_dump_format(oc, 0, filename, 1);
yading@10: 
yading@10:     /* open the output file, if needed */
yading@10:     if (!(fmt->flags & AVFMT_NOFILE)) {
yading@10:         ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
yading@10:         if (ret < 0) {
yading@10:             fprintf(stderr, "Could not open '%s': %s\n", filename,
yading@10:                     av_err2str(ret));
yading@10:             return 1;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     /* Write the stream header, if any. */
yading@10:     ret = avformat_write_header(oc, NULL);
yading@10:     if (ret < 0) {
yading@10:         fprintf(stderr, "Error occurred when opening output file: %s\n",
yading@10:                 av_err2str(ret));
yading@10:         return 1;
yading@10:     }
yading@10: 
yading@10:     if (frame)
yading@10:         frame->pts = 0;
yading@10:     for (;;) {
yading@10:         /* Compute current audio and video time. */
yading@10:         if (audio_st)
yading@10:             audio_pts = (double)audio_st->pts.val * audio_st->time_base.num / audio_st->time_base.den;
yading@10:         else
yading@10:             audio_pts = 0.0;
yading@10: 
yading@10:         if (video_st)
yading@10:             video_pts = (double)video_st->pts.val * video_st->time_base.num /
yading@10:                         video_st->time_base.den;
yading@10:         else
yading@10:             video_pts = 0.0;
yading@10: 
yading@10:         if ((!audio_st || audio_pts >= STREAM_DURATION) &&
yading@10:             (!video_st || video_pts >= STREAM_DURATION))
yading@10:             break;
yading@10: 
yading@10:         /* write interleaved audio and video frames */
yading@10:         if (!video_st || (video_st && audio_st && audio_pts < video_pts)) {
yading@10:             write_audio_frame(oc, audio_st);
yading@10:         } else {
yading@10:             write_video_frame(oc, video_st);
yading@10:             frame->pts += av_rescale_q(1, video_st->codec->time_base, video_st->time_base);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     /* Write the trailer, if any. The trailer must be written before you
yading@10:      * close the CodecContexts open when you wrote the header; otherwise
yading@10:      * av_write_trailer() may try to use memory that was freed on
yading@10:      * av_codec_close(). */
yading@10:     av_write_trailer(oc);
yading@10: 
yading@10:     /* Close each codec. */
yading@10:     if (video_st)
yading@10:         close_video(oc, video_st);
yading@10:     if (audio_st)
yading@10:         close_audio(oc, audio_st);
yading@10: 
yading@10:     if (!(fmt->flags & AVFMT_NOFILE))
yading@10:         /* Close the output file. */
yading@10:         avio_close(oc->pb);
yading@10: 
yading@10:     /* free the stream */
yading@10:     avformat_free_context(oc);
yading@10: 
yading@10:     return 0;
yading@10: }