February 2008 - ffmpeg-user - lists.ffmpeg.org

ffmpeg web mixer project (last attempt to send this mail...)
by mario＠sgrunt.net 29 Feb '08

29 Feb '08

Hi all. I'm sending this mail again... I don't know why... but gmail decided to trunk my previous posts. Sorry AGAIN about that... I have to develop a little web application using ffmpeg as video engine. In this app there are many live streamed video (from webcams) sent to a web server. On this web server there is a ffmpeg based cgi program that get one of these stream and publish it as a flv/mov file (for a flash player). >From a web interface it is possilbe (driving the ffmpeg based program) to switch among the streamed source choosing which webcam to publish. The prototype made in PHP with ffmpeg called from the command line went well. Now it's time to develop a serious C app. What I want to do is a simple stream proxy: my app should get one A/V stream as input and send it to the browser(s) on demand. The C app scheleton (CGI IPC... connections stuff...) is done, but I'm stucked on the ffmpeg API (I started from output_example.c) Now the questions: - At the beginng, my proxy was really stupid: it took the stream from a TCP socket (source) and it sent it to another socket (flash player http call). Without understanding what It was reading. It didn't work. Then I decided to use ffmpeg, so my app now knows what it is doing. Am I in the rigth way or it is possible to do a blind "NAT" with streams, and I failed for other reasons? Stream was flv1 or h264. - With the help of vlc I have successfully streamed a webcam to a flash player. VLC can handle http request and generate fake infinite flv files. I couldn't do the save with h264 format (problems generating the video ). Doubt: all my succeeded h264 tests was made streaming an entire file: from the beginning to the end. Am I now failing because it's not possibile to "join" a previous started h264 stream and I must send some special header to make the flash player happy? If yes: can I do that with the ffmpeg API ? Or.. if this is a stupid question... where can I read something to understand? Tnx for the attention. Mario

1 0

FFMpeg- Mpg file is black screen
by hongyin.lim＠gmail.com 29 Feb '08

29 Feb '08

Hi, I am new to the ffmpeg application. When I tried to run the ffmpeg application to capture video from my capture card, I only get black screen when I view the .mpg file. The information of the AV capture card is (from dmesg): saa7134 ALSA driver for DMA sound unloaded saa7130/34: v4l2 driver version 0.2.14 loaded saa7133[0]: found at 0000:03:0e.0, rev: 209, irq: 20, latency: 64, mmio: 0xff7ff800 saa7133[0]: subsystem: 16be:0010, board: Terratec Cinergy HT PCI [card=108,insmod option] saa7133[0]: board init: gpio is 0 saa7133[0]: i2c eeprom 00: be 16 10 00 54 20 1c 00 43 43 a9 1c 55 d2 b2 92 saa7133[0]: i2c eeprom 10: 00 ff 86 0f ff 20 ff 00 01 50 32 79 01 3c ca 50 saa7133[0]: i2c eeprom 20: 01 40 01 02 02 03 01 00 06 ff 00 2c 02 51 96 2b saa7133[0]: i2c eeprom 30: a7 58 7a 1f 03 8e 84 5e da 7a 04 b3 05 87 b2 3c saa7133[0]: i2c eeprom 40: ff 21 00 c0 96 10 03 22 15 00 fd 79 44 9f c2 8f saa7133[0]: i2c eeprom 50: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff saa7133[0]: i2c eeprom 60: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff saa7133[0]: i2c eeprom 70: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff tuner 1-004b: chip found @ 0x96 (saa7133[0]) tuner 1-004b: setting tuner address to 60 tuner 1-004b: type set to tda8290+75a tuner 1-004b: setting tuner address to 60 tuner 1-004b: type set to tda8290+75a saa7133[0]: registered device video0 [v4l2] saa7133[0]: registered device vbi0 saa7134 ALSA driver for DMA sound loaded saa7133[0]/alsa: saa7133[0] at 0xff7ff800 irq 20 registered as card -1 The command I tried to run: > ffmpeg -f video4linux2 -s qvga -tvstd ntsc -an -r 24 -i /dev/video0 test.mpg This is the output: FFmpeg version SVN-r12276, Copyright (c) 2000-2008 Fabrice Bellard, et al. configuration: libavutil version: 49.6.0 libavcodec version: 51.50.1 libavformat version: 52.7.0 libavdevice version: 52.0.0 built on Feb 29 2008 15:54:35, gcc: 4.1.1 20061011 (Red Hat 4.1.1-30) [video4linux2 @ 0x8421b30][3]Capabilities: 5010015 Input #0, video4linux2, from '/dev/video0': Duration: N/A, start: 1204280309.866328, bitrate: 22118 kb/s Stream #0.0: Video: rawvideo, yuv420p, 320x240 [PAR 0:1 DAR 0:1], 22118 kb/s, 24.00 tb(r) Output #0, mpeg, to 'test.mpg': Stream #0.0: Video: mpeg1video, yuv420p, 320x240 [PAR 0:1 DAR 0:1], q=2-31, 200 kb/s, 24.00 tb(c) Stream mapping: Stream #0.0 -> #0.0 Press [q] to stop encoding frame= 271 fps= 31 q=2.0 Lsize= 158kB time=11.2 bitrate= 115.1kbits/s Is there any thing wrong with my program? Thank you very much. Regards, hy

1 0

a little off topic - thought I would ask
by jshupert＠pps-inc.com 29 Feb '08

29 Feb '08

Friends, I wonder if anyone knows of a software that I could use to analyze mpeg headers. That is something that will tell me about the MPEG system table at the beginning of a stream. I wish to be able to know the length of the packet ( like 12 bytes) and decern if it is legal ( or illegal only 9 bytes ) I wish to have info on system headers . I have found this http://ardmore.net/~thepaces/vk_tools/index.html and I was wondering if anyone else has used it? thanks! jim

2 1

encoding to WMV9
by james.strickland＠strickstuff.com 28 Feb '08

28 Feb '08

Greetings all, Is it possible to encode to WMV9 format? If so, how would I go about doing it. Can't seem to find anything in the documentation. PURPOSE: to (re)encode video for play on my zune. without having to be re-encoded by the Zune Software. Thanks, James Strickland Misawa AB, Japan www.StrickStuff.com

2 1

ffmpeg web mixer project (prev mail was incomplete)
by dodiesis＠gmail.com 28 Feb '08

28 Feb '08

Hi all. I'm sending this mail again... I don't know why... but gmail decided to trunk my previous post. Sorry about that... I have to develop a little web application using ffmpeg as video engine. In this app there are many live streamed video (from webcams) sent to a web server. On this web server there is a ffmpeg based cgi program that get one of these stream and publish it as a flv/mov file (for a flash player) >From a web interface it is possilbe (driving the ffmpeg based program) to switch among the streamed source choosing which webcam to publish. The prototype made in PHP with ffmpeg called from the command line went well. Now it' time to develop a serious C app. What I want to do is a simple stream proxy: my app should get one A/V stream as input and send it to the browser(s) on demand. The C app scheleton (CGI IPC... connections stuff...) is done, but I'm stucked on the ffmpeg API (I started from output_example.c) Now the questions: - At the beginng, my proxy was really stupid: it took the stream from a TCP socket (source) and it sent it to another socket (flash player http call). Without understanding what It was reading. It didn't work. Then I decided to use ffmpeg, so my app now knows what it is doing. Am I in the rigth way or it is possible to do a blind "NAT" with streams, and I failed for other reasons? Stream was flv1 or h264. - With the help of vlc I have successfully streamed a webcam to a flash player. VLC can handle http request and generate fake infinite flv files. I couldn't do the save with h264 format (problems generating the video ). Doubt: all my succeeded h264 tests was made streaming an entire file: from the beginning to the end. Am I now failing because it's not possibile to "join" a previous started h264 stream and I must send some special header to make the flash player happy? If yes: can I do that with the ffmpeg API ? Or.. if this is a stupid question... where can I read something to understand? Tnx for the attention. Mario -- Mario Signorino | www.sgrunt.net

1 0

mpeg version option for aac?
by jujulj＠gmail.com 28 Feb '08

28 Feb '08

hi, how can I set the mpeg version of the aac encoder in ffmpeg (something like --mpeg-vers option in faac)? thanks! jul

1 0

trying to append a empty raw video stream at the end with ffmpeg
by tadracko＠gmail.com 28 Feb '08

28 Feb '08

I'm trying to append a blank/empty video stream at the end when encoding to a flv file as result of this test with ffmpeg: ffmpeg -f rawvideo -pix_fmt rgb24 -s 320x240 -r 30000/1001 -i /dev/zero -f yuv4mpegpipe -pix_fmt yuv420p -y out.yuv this command produces a blank video stream from /dev/zero Then I tried this: ffmpeg -i resident\ evil\ 4\ pre-release\ trailer.wmv -f rawvideo -pix_fmt rgb24 -s 480x360 -r 30000/1001 -i /dev/zero -b 250k -ab 96k -f flv -vcodec flv -t 00:10:00 out.flv but it didn't work, it only encodes the first video without appending the second video source, I still don't know if this something possible with ffmpeg, I dont know if it's because the blank video stream doesn't has any audio..

2 1

Strange audio problem coding flv files.
by john＠jcoppens.com 27 Feb '08

27 Feb '08

Hello people. I have been trying for a couple of hours to convert an AVI into a FLV movie. And though I've done this quite a few times before, this is the first time I'm blocked. The audio on the FLV file has 'ticks' in it (about twice a second), and the audio is garbled. I'm suspecting that the frame rate of the original avi (encoded with mencoder from a DVD documentary) changes frame rates, and the audio doesn't follow, but don't take me up on that theory. ffmpeg is the latest download from SVN (today). This is the output of mplayer starting up, showing the original AVI file: Playing Wetlands.avi. AVI file format detected. [aviheader] Video stream found, -vid 0 [aviheader] Audio stream found, -aid 1 AVI: ODML: Building ODML index (2 superindexchunks). VIDEO: [FMP4] 720x576 24bpp 25.000 fps 2199.9 kbps (268.5 kbyte/s) Clip info: Software: MEncoder 1.0rc2-4.1.2 ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4) ========================================================================== ========================================================================== Opening audio decoder: [pcm] Uncompressed PCM audio decoder AUDIO: 48000 Hz, 2 ch, s16le, 1536.0 kbit/100.00% (ratio: 192000->192000) Selected audio codec: [pcm] afm: pcm (Uncompressed PCM) ========================================================================== AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample) Starting playback... VDec: vo config request - 720 x 576 (preferred colorspace: Planar YV12) Could not find matching colorspace - retrying with -vf scale... Opening video filter: [scale] VDec: using Planar YV12 as output csp (no 0) Movie-Aspect is 2.00:1 - prescaling to correct movie aspect. [swscaler @ 0x88b1810]SwScaler: using unscaled yuv420p -> bgr24 special converter VO: [gl2] 720x576 => 1152x576 BGR 24-bit [gl2] You have OpenGL >= 1.2 capable drivers, GOOD (16bpp and BGR is ok!) [gl2] antialiasing off [gl2] bilinear linear A: 2.2 V: 2.2 A-V: -0.004 ct: 0.006 57/ 57 13% 20% 0.1% 1 0 Exiting... (Quit) ------------- I ran several (many, in fact) combinations of the following conversion command: ffmpeg -i Wetlands.avi -ar 22050 -ab 56 -acodec libmp3lame -b 300k -f flv -s 428x240 -ac 1 Wetlands.flv tried other -ar rates, -ab 56k, the -s with different sizes, etc. When starting mplayer on the resulting FLV: Playing Wetlands.flv. libavformat file format detected. [lavf] Video stream found, -vid 0 [lavf] Audio stream found, -aid 1 VIDEO: [FLV1] 428x240 0bpp 25.000 fps 0.0 kbps ( 0.0 kbyte/s) ========================================================================== Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family Selected video codec: [ffflv] vfm: ffmpeg (FFmpeg Flash video) ========================================================================== ========================================================================== Opening audio decoder: [mp3lib] MPEG layer-2, layer-3 AUDIO: 22050 Hz, 2 ch, s16le, 32.0 kbit/4.54% (ratio: 4000->88200) Selected audio codec: [mp3] afm: mp3lib (mp3lib MPEG layer-2, layer-3) ========================================================================== AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample) Starting playback... VDec: vo config request - 428 x 240 (preferred colorspace: Planar YV12) Could not find matching colorspace - retrying with -vf scale... Opening video filter: [scale] VDec: using Planar YV12 as output csp (no 0) Movie-Aspect is undefined - no prescaling applied. [swscaler @ 0x88b1810]SwScaler: using unscaled yuv420p -> bgr24 special converter VO: [gl2] 428x240 => 428x240 BGR 24-bit [gl2] You have OpenGL >= 1.2 capable drivers, GOOD (16bpp and BGR is ok!) [gl2] antialiasing off [gl2] bilinear linear A: 3.2 V: 3.2 A-V: 0.012 ct: 0.000 81/ 81 4% 5% 1.2% 0 0 Exiting... (Quit) ---------- ffplay doesn't like the resulting flv either... Any suggestions would be appreciated! John

3 13

FFMPEG on multiprocessor machine
by rodrigo.schramm＠gmail.com 27 Feb '08

27 Feb '08

Hello, How can I run the ffmpeg program in a machine with 4 processors? When I execute the ffmpeg, only 1 processor is utilized. I need to compile it with especial flags? Schramm

4 4

Remuxing h264 video into mp4 for xbox 360
by tjordan＠macrosystem.de 27 Feb '08

27 Feb '08

Hello all, i am trying to use DVB broadcasted HDTV (h264) into mp4 files playable by xbox 360. It works with ffmpeg, but the result gives jerky playback, it seems that playback jitters around correct frame order, as if two consecutive frames are swapped in playback. I tried other time stamp computation (using libavformat directly) and many more, but no difference. When i mux the h264 elementary stream with mpeg4creator from the mpeg4ip project it works, smooth playback. Does anyone know what could be the problem here? missing feature in libavformat's mp4 muxer? parameters to AVFormatContext? any help welcome! -- Regards, Thorsten

2 1