Sorry, I'm back again. I still would like to do my video editing with glav and sound. Consequently I did a lot of research and Gentoo Forum message exchanges about alsa and OSS. I tried to resolve the issue without turning to this mailing list community. Here is the latest situation, and now I'm asking for comments, suggestions.
After enabling /dev/dsp and making sure that alsa oss emulation is configured correctly - quote: janos@andraslinux ~/save/tmp/videoDigitizing $ glav xcoded.avi ++: **ERROR: [lavplay] Error initializing Audio: Audio task died. Reason: Error: Soundcard fragment size unexpected ++: lavtools version 2.2.1 janos@andraslinux ~/save/tmp/videoDigitizing $ aoss glav xcoded.avi ++: **ERROR: [lavplay] Error initializing Audio: Audio task died. Reason: Error: Invalid argument - mapping audio buffer (consider using read/write instead of mmap) ++: lavtools version 2.2.1 Unquote. Apparently something is wrong either with "fragment size". I could probably configure fragment size if I knew what lavplay expects; the loaded modules are: snd_pcm_oss snd_mixer_oss or something is wrong with in the code of lavplay. Greetings to all, Janos/jankom -- Janos G. Komaromi sent it NOT from iPhone nor Google facebook, instagram, viber, snapchat, twitter, #@*~| etc. - neither of those https://jgklinux.jankom.net/ On Sun, 2022-10-23 at 18:58 -0400, Janos G Komaromi wrote: > Hi Bernie, > > I did a little research and math. > > (1) The original video was recorded with a "Canovision 8" camcorder > purchased in the mid-80s. The spec says the CCD is 1/3 inch with 320k > pixels. This particular camera was made for the US (American) > market, and it has a simple RCA one vido and one RCA mono outputs. > Connecting it to an old TV set (NTSC) it provided a decent video > play. > My digitazing device (ION Video 2 SD) has one RCA video input and two > RCA stereo inputs (I used an RCA "Y" connector to provide fake stereo > input to the device). The ezcap0001.avi file created by the device > does indeed have the strange 800x592 resolution. OK, but it is almost > 4:3 or 800:600. > > (2) One of the standard Aspect Ratios of Digital Videos is 4/3. If > the > Canovision camera has 320k pixels then for a 4/3 AR of the mid 80s TV > sets the video output of the camera must have 692.82x461.88 > pixel output. Apparently the ION device converted it to 800x592. I > don't know how and why, but that's OK The discrepancy between 600 and > 592 must be to the zooming algorithm designed into the ION software. > As > far as the compression methods (various audio and video mp???, etc.) > are > concerned - again, it is designed into the resulting digital file > format of ezcapnnnn.avi. > > (3) I decided to use ffmpeg to transcode the ezcap... file: > ffmpeg -i ezcap0001.avi -vcodec mjpeg -acodec pcm_s16le x.avi > and then use glav for editing (had to use -a 0 because of the dsp > issue > -later), and IT WORKED! The video looks good, good aspect ratio (not > squeezed horizontally or vertically). > > I think, I'm all set for now. This was a good learning experience. > > Thanks again, > > Janos > _______________________________________________ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
