FFmpeg中ffplay源代码的修改

mp4

已解决

mp4

刚找了个FFmpeg编程指南（How to Write a Video Player in Less Than 1000 Lines）
http://www.dranger.com/ffmpeg/

里面第一个示例程序编译就通不过
root:~/ffmpeg# gcc -o tutorial01 tutorial01.c -lavutil -lavformat -lavcodec -lz -lavutil -lm
tutorial01.c: In function 'main':
tutorial01.c:82: error: invalid type argument of '->'
tutorial01.c:90: error: incompatible types in assignment
郁闷。。。

bushuhui

为什么不试试mplayer呢？

随风缘

在 av_read_frame 函数执行失败的时候调用exit就行了.

mp4

原帖由 bushuhui 于 2008-9-22 12:49 发表
为什么不试试mplayer呢？

mplayer播放完后会自动退出，也可以按q键退出，不过太庞大了，不想杀鸡用牛刀，而且mplayer用的也是FFmpeg的源代码

mp4

原帖由 随风缘 于 2008-9-22 13:12 发表
在 av_read_frame 函数执行失败的时候调用exit就行了.

我当初也是这么改的，不管用啊

我找到循环读数据的那段，加了两句：
     printf("\a\n");
       goto fail;
结果一运行就马上退出，什么声音都还没播出

/* this thread gets the stream from the disk or the network */ static int decode_thread(void *arg) { 。。。 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ret = av_read_frame(ic, pkt); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if (ret < 0) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;printf("\a\n"); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;goto fail; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if (url_ferror(&ic->pb) == 0) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SDL_Delay(100); /* wait for user event */ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;continue; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} else &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;break; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} 。。。 fail: &nbsp;&nbsp;&nbsp;&nbsp;/* disable interrupting */ &nbsp;&nbsp;&nbsp;&nbsp;global_video_state = NULL; &nbsp;&nbsp;&nbsp;&nbsp;/* close each stream */ &nbsp;&nbsp;&nbsp;&nbsp;if (is->audio_stream >= 0) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;stream_component_close(is, is->audio_stream); &nbsp;&nbsp;&nbsp;&nbsp;if (is->video_stream >= 0) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;stream_component_close(is, is->video_stream); &nbsp;&nbsp;&nbsp;&nbsp;if (is->subtitle_stream >= 0) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;stream_component_close(is, is->subtitle_stream); &nbsp;&nbsp;&nbsp;&nbsp;if (is->ic) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;av_close_input_file(is->ic); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;is->ic = NULL; /* safety */ &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;url_set_interrupt_cb(NULL); &nbsp;&nbsp;&nbsp;&nbsp;if (ret != 0) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SDL_Event event; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;event.type = FF_QUIT_EVENT; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;event.user.data1 = is; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SDL_PushEvent(&event); &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;return 0; }

把那两句加到continue后，结果和没改过一样，看了下av_read_frame接口函数的说明，返值小于0就是遇到文件尾了啊？

int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream. The information is stored as a packet in pkt.

The returned packet is valid until the next av_read_frame() or until av_close_input_file() and must be freed with av_free_packet. For video, the packet contains exactly one frame. For audio, it contains an integer number of frames if each frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames have a variable size (e.g. MPEG audio), then it contains one frame.

pkt->pts, pkt->dts and pkt->duration are always set to correct values in AVStream.timebase units (and guessed if the format cannot provided them). pkt->pts can be AV_NOPTS_VALUE if the video format has B frames, so it is better to rely on pkt->dts if you do not decompress the payload.

Returns: 0 if OK, < 0 if error or end of file.

mp4

Hacker高手怎么还没出现啊？我再追加悬赏20分！

红外接收头电路图，成本不超过5块钱

mq110

原帖由 mp4 于 2008-9-22 20:15 发表


我当初也是这么改的，不管用啊

我找到循环读数据的那段，加了两句：
     printf("\a\n");
       goto fail;
结果一运行就马上退出，什么声音都还没播出

/* this thread gets the stream from th ...

不会啊,av_read_frame到文件尾了,就返回小于0了. 那个时候exit当然可以了.