hi all ...
i'm currently working with a gem patch to play back videos files encoded with the cinepak format on linux ...
i'm using pix_film (gem-0.90), aviplay and iccvid.dll ...
but somewhere there is a memory leak (not sure, where), that makes the machines crash after 20 to 30 minutes, because it goes out of memory ...
any idea, what's the source of that? and what's the prefered (most stable, hq) video codec for linux ...
thanks .... tim
hi tim,
sorry can't help you with the memory leak... but
i'm looking too for the best video codec for linux/gem. since libdv is really slow on linux (expensive on the cpu), i have to encode my footage, but i want to keep a good resolution (640x480). so, i did some test with lots of formats and codecs. the best codec for quality and not too expensive on cpu is avi :: rawvideo (yuv i think). but the colors of the video in gem are bad (rainbow)...
so, i tried mpeg2. it's loading fine, but there's a problem: gem can't loop it, i have to reload the video. maybe it's the way i encoded it (using ffmpeg). some people say that motionjpeg with quicktime is the best, but not for a 640x480 video...
still doing some research, i'll let you know and let me know! pat
Hello!
here's my 2 cents on video codecs on linux:
I like MJPEG since it's still quite fast in full pal ( ntsc) compared to DV. If I want to be cheap, I recode the dv to quarterpal ( 352x288) mjpeg, wich in my opinion doesn't look much worse then dv already does. Keep multiples of 16 and you can go steps in-between easily ( eg 512x480 something works too ). Using the mjpegtools ( mjpeg.sf.net ) you can do editlist preprocessing of material, and I love mplayer's filters for brightness contrast and so on. Play the output to a yuvpipe ( fifo) and reencode them using the mjpegtools I get the most quality. DV codec on linux is useless for anything that has to be even near-realtime.
Still mjpeg is demanding. Maybe there's a way to use mpeg4 with only I-frames. compression is not really visible but decompressing really fast. I use it in veejay or a compressed-yuv inside an avi container but I don't know if it's available in gem ( its a veejay only codec for realtime stuff ). PhotoJPEG seems to work too but more for the macos platform (?). MPEG4 with i-frames only( so you can do trickplay too) and little compression is really not that bad ( compared to the original dv uglyness or mpeg2 ). if it can play in gem, try options of mencoder/mplayer, I think you can fix it to make I-frames every frame.
oh, motion jpeg doesn't differ in either quicktime or avi. it's just a container. the ffmpeg codec is a bit faster then the mjpeg.sf.net one.
codec hell!
cheers! mvh
patrick wrote:
hi tim,
sorry can't help you with the memory leak... but
i'm looking too for the best video codec for linux/gem. since libdv is really slow on linux (expensive on the cpu), i have to encode my footage, but i want to keep a good resolution (640x480). so, i did some test with lots of formats and codecs. the best codec for quality and not too expensive on cpu is avi :: rawvideo (yuv i think). but the colors of the video in gem are bad (rainbow)...
so, i tried mpeg2. it's loading fine, but there's a problem: gem can't loop it, i have to reload the video. maybe it's the way i encoded it (using ffmpeg). some people say that motionjpeg with quicktime is the best, but not for a 640x480 video...
still doing some research, i'll let you know and let me know! pat
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patrick wrote:
hi tim,
so, i tried mpeg2. it's loading fine, but there's a problem: gem can't loop it, i have to reload the video. maybe it's the way i encoded it (using
oh that one is simple: you have to create an external index file of all the keyframes for your mpeg2. this is: get mpeg3toc (on debian this is part of mpeg3-utils but i have no idea where it could be on other distros ...) run "mpeg3toc <mpegfile> <tocfile>" and load the tocfile(!) instead of the mpegfile; then you can do frame accurate seeking and everything
mfg.a.dr IOhannes
and load the tocfile(!) instead of the mpegfile; then you can do frame accurate seeking and everything
hi IOhannes,
done that (mpeg3toc my mpeg2 movie), but when i open it in (GEM: ver: 0.90 / Linux) it crash big time: no error. tried with pix_film and pix_movie.
should i run gdm to help you find why? (but, i don't know how).
patrick
photo jpeg should be the best codec for performance!!!!
Just the biggest file sizes...
(at least on linux)
I have an installation using gem 0.79 that has been up for years without problems mixing four videos using this codec.
B>
Patrick: For MPEG2 the delta compression may be screwing up the frame seeking... ? some codecs only play forward well, and awfully backward.
patrick wrote:
hi tim,
sorry can't help you with the memory leak... but
i'm looking too for the best video codec for linux/gem. since libdv is really slow on linux (expensive on the cpu), i have to encode my footage, but i want to keep a good resolution (640x480). so, i did some test with lots of formats and codecs. the best codec for quality and not too expensive on cpu is avi :: rawvideo (yuv i think). but the colors of the video in gem are bad (rainbow)...
so, i tried mpeg2. it's loading fine, but there's a problem: gem can't loop it, i have to reload the video. maybe it's the way i encoded it (using ffmpeg). some people say that motionjpeg with quicktime is the best, but not for a 640x480 video...
still doing some research, i'll let you know and let me know! pat
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On Mar 17, 2005, at 2:53 PM, Tim Blechmann wrote:
hi all ...
i'm currently working with a gem patch to play back videos files encoded with the cinepak format on linux ...
Why on earth are you doing that? Cinepak is the very first lossy codec
developed for quicktime around 1991 and the quality is horrendous.
It's very unlikely that you would encounter any content compressed
after 1996/97 in Cinepak as literally every single codec after it is
superior.
and what's the prefered (most stable, hq) video codec for linux ...
Photo-Jpeg? Uncompressed 4:2:2? Anything other than Cinepak!
thanks .... tim
hm ... i converted all the movies to divx ... same memory leak :-(
won't have a lot of time to investigate any more ...
anyway ... thanks for you hints ...
cheers .... t
i agree that cinepak looks terrible, but i feel like i'm stuck using it because:
- the files are relatively small and they decompress quickly, so i can
play many of them simultaneously
- i can keyframe every single frame, so i don't get any hiccups
scrubbing/scratching the video
so what i'm asking is:
given that i want to be able to play back many (at least four) video files simultaneously while manipulating their playback speeds and directions (like scratching records on turntables), what is the best codec to use?
also am i making incorrect assumptions given the capabilities of modern hardware? that is, do i really need to keyframe every single frame in order to get smooth playback in both directions and at rapidly varying speeds? and do i really need to be concerned with having file sizes small enough to reside in memory and not streamed from disk? _ j
chris clepper wrote:
On Mar 17, 2005, at 2:53 PM, Tim Blechmann wrote:
hi all ...
i'm currently working with a gem patch to play back videos files encoded with the cinepak format on linux ...
Why on earth are you doing that? Cinepak is the very first lossy codec developed for quicktime around 1991 and the quality is horrendous. It's very unlikely that you would encounter any content compressed after 1996/97 in Cinepak as literally every single codec after it is superior.
and what's the prefered (most stable, hq) video codec for linux ...
Photo-Jpeg? Uncompressed 4:2:2? Anything other than Cinepak!
thanks .... tim
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/
[/(o)][:+:][/(o)] http://justincrounds.org/ __________________________
Datarate is the real problem here.
If this is what you do visually then spec your HW to do this. Try putting two clips on one drive (not partition) and the other two on another. That should double your datarate for disk access. 7200 RPM drives are faster too, SCSI or SATA... beats old IDE.. check your DMA modes...
You have two problems. Datarate is the first, and loading will be slower if you can't get the pixels off the drive and onto your texture fast enough (which means that depending on the resolution your gfx card APG speed may make a difference.
Second problem is the CPU usage it takes to decode a frame. There are fast photojpeg decoder libs (with optimization) and on macOS most things are super fast...
On an old 800MHZ PC with a single drive I could mix two videos at a time, but there were four videos in the schene, just only two visible at any given moment. When one was invisible it stopped playing but was still in the scene.
My videos were photoJPG 256x256 pixels.
B.
justin c. rounds wrote:
i agree that cinepak looks terrible, but i feel like i'm stuck using it because:
- the files are relatively small and they decompress quickly, so i can
play many of them simultaneously
- i can keyframe every single frame, so i don't get any hiccups
scrubbing/scratching the video
so what i'm asking is:
given that i want to be able to play back many (at least four) video files simultaneously while manipulating their playback speeds and directions (like scratching records on turntables), what is the best codec to use?
also am i making incorrect assumptions given the capabilities of modern hardware? that is, do i really need to keyframe every single frame in order to get smooth playback in both directions and at rapidly varying speeds? and do i really need to be concerned with having file sizes small enough to reside in memory and not streamed from disk? _ j
chris clepper wrote:
On Mar 17, 2005, at 2:53 PM, Tim Blechmann wrote:
hi all ...
i'm currently working with a gem patch to play back videos files encoded with the cinepak format on linux ...
Why on earth are you doing that? Cinepak is the very first lossy codec developed for quicktime around 1991 and the quality is horrendous. It's very unlikely that you would encounter any content compressed after 1996/97 in Cinepak as literally every single codec after it is superior.
and what's the prefered (most stable, hq) video codec for linux ...
Photo-Jpeg? Uncompressed 4:2:2? Anything other than Cinepak!
thanks .... tim
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B. Bogart -
chris clepper -
IOhannes m zmoelnig -
justin c. rounds -
MvH -
patrick -
patrick -
Tim Blechmann