Hi, I'm testing a program using AVIOContext to extract some frames of a video, I need to use an InputStream not a URL. I'm using the source code of avio_reading.c to test my sample videos ( https://www.ffmpeg.org/doxygen/trunk/avio__reading_8c_source.html)
I tested this program with video1.wmv without any problems. After that I converted video1.wmv into some video formats like mp4, mov, asf, and avi I got some errors only with mp4 and mov videos, the error is the same in both cases: [mov,mp4,m4a,3gp,3g2,mj2 @ 0x188ed00] stream 0, offset 0x30: partial file [mov,mp4,m4a,3gp,3g2,mj2 @ 0x188ed00] Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none, 960x540, 728 kb/s): unspecified pixel format Consider increasing the value for the 'analyzeduration' and 'probesize' options I have tried to increase these values without success. Looking into the output of this program, I noticed that all video is scanned in order to find these parameters. So, I think the problem is that some metadata are lost when I converted from wmv to mp4. I used this command to convert ffmpeg -i video1.wmv -q:v 0 -vcodec libx264 -pix_fmt yuv420p video1.mp4 this is the output of av_dump_format using C program Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'videos/bigdata.mp4': Metadata: major_brand : isom minor_version : 512 compatible_brands: isomiso2avc1mp41 encoder : Lavf56.25.101 Duration: 00:01:07.02, bitrate: N/A Stream #0:0(eng): Video: h264 (avc1 / 0x31637661), none, 960x540, 728 kb/s, 30 fps, 30 tbr, 15360 tbn (default) Metadata: handler_name : VideoHandler Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 32000 Hz, 2 channels, 93 kb/s (default) Metadata: handler_name : SoundHandler As you can see, there is a "none" value, but I don't know how to fix this. However, I tested this video without using an AVIOContext, and it works fine. Also, I tested it using ffmpeg command and also it works. Finally this is the output of ffmpeg -i with this same video. Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'videos/video1.mp4': Metadata: major_brand : isom minor_version : 512 compatible_brands: isomiso2avc1mp41 encoder : Lavf56.25.101 Duration: 00:01:07.02, start: 0.064000, bitrate: 824 kb/s Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x540, 728 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default) Metadata: handler_name : VideoHandler Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 32000 Hz, stereo, fltp, 93 kb/s (default) Metadata: handler_name : SoundHandler What do you think ? I'm missing something when converting the video, or I need to add some lines in avio_reading.c ? I'm using ffmpeg 2.6.2 thanks _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel