Been playing with numerous tools over the last few years, and whilst i'm reasonably happy with the quality i'm getting at the moment, it still isn't quite there.
HW - Athlon XP 2.8, SAA7134 based capture, TNT2-M64 graphics, 512Mb Ram.
OS - RedHat 9.0 with a 2.4.26 kernel with v4l2/saa7134 patches
Storage - 80 Gb Seagate 7200 rpm ATA 100 HD (capture only, additional drives present for system and long term storage) - dedicated ide channel.
Now I know the graphics card is a little ancient but hey it works well enough for my editing.
Requirements
------------
Full screen D1 PAL Capture with 48000Hz Audio, to be transcoded into DVD. Zero frame drops or under 5 frames/hour. Accurate sync. Lossless, or close to lossless.
Tools - Capture
---------------
ffmpeg - Never happy with the level of control or the poor v4l2 support when i've tried it in the past. Has this gotten a lot better. Remember the frame drop requirements.
mencoder - Also strange v4l2 problems so I haven't used it in quite some time.
lavrec - Way too many frame drops. Don't understand why. Can someone give me some tips on how to best tweak this.
nvrec - Used this for quite a while, especially when some of the ffmpeg codecs worked with it. Generally ok at 1/2 D1 but struggled at D1. Used to capture 1/2 D2 to produce CVD disks, but aiming for DVD quality now.
ffv1rec - A by-product of the avidemux tools (http://avidemux.sf.net). Based on nvrec (nuppel container) with a lot of codecs supported (MJPEG, HUFFYUV, FFV1, MPEG4, XVID). Now this tool i've used the most of late and so i'll talk about it a bit more. It has all the great sync features of nuvec with the added bonus of better codec support. Plus 'mean' is a great developer.
ffv1rec + FFV1 - Hammers the hell out of the machine. Requires too much CPU but produces great size lossless files. Speeding this code up (a lot) would be wonderful
ffv1rec + HUFFYUV - Great quality, hammers the HD instead. Had some RAID 0 problems so i've dropped back to a single drive at the moment. Ok for shows upto 30 minutes but after thay I usually get loads of frame drops.
ffv1rec + MPEG4 - Using the ffmpeg MPEG4 support is pretty damn awesome. Biggest problem are badly encoded interlaced artifacts. Turning on the interlaced video support is usually too much of a CPU hit.
ffv1rec + XVID - Similar to MPEG4. Some people prefer it. Haven't tried it with XVID 1.0 yet.
ffv1rec + MJPEG - Currenly my standard for longer captures (over 1/2 hr) but even though I use the highest quality setting i'm not happy with the video. Too many problems with dark areas, but better handling of interlaced video than MPEG4
ffv1rec + LJPEG - modified the source to add Lossless MJPEG support. Great video but not enought CPU. Real shame.
ffv1rec + MPEG2 - Again tried to modify the source, but haven't got it working yet.
Tools - Editing/Tweaking
------------------------
MPlayer - Together with mencoder. Great at tweaking/playing broken video streams.
ffmpeg - Need I say more. Awesome guys
Avidemux2 - Currently the only gui based tool I generally use. Plus the only tool that reads the ffv1rec nuppel based files. Great VirtualDub style tool (cheers mean). The filters here really help clean things up.
lverequant - Great for shrinking MPEG2 encodes slightly and quickly to fit on a DVD.
dvdauthor - Well I am aiming for DVD aren't I.
Editing Process
---------------
Typical process to produce a decent DVD capable MPEG2.
1. Load ffv1rec generated nuppel video file into avidemux2 and produce index.
2. Clean up the framing by blackening borders or junke, and hard framing if it is widescreen.
3. Take out adverts (oh the joys of commercial television) or clean up edits.
4. Add a deinterlace filter if video is suitable - improves compression dramatically if the video source is clean enough
5. Add a decent filter to clean up colour issues etc (gotta luv capturing on a windy night).
6. Render Audio to decent rate AC3 (192k or above)
7. Render Video to suitable size MPEG2 file (between 1Gb and 1.3Gb for a typical 45 Minute show).
8. Mplex to a DVD MPG file and burn away.
The Issues
----------
1. The better quality codecs keep resulting in frame drops. Some due to CPU (FFV1 + LJPEG) others due to data rate (HUFFYUV).
2. No equivalent to the high performance lossless MJPEG codecs available on windows like PicVideo.
3. Current solutions (MJPEG / MPEG4 / XVID) have interlace video issues or dark area encoding problems.
4. No suitable real-time software MPEG2 solution at this stage.
5. FFMPEG has a much quicker MPEG2 renderer than MJPEG Tools, but it still isn't quite standards compliant enough for my Philips DVD 711.
Solutions ? -----------
1. Software equivalent to Current HW MPEG2 solutions. Capture at high bitrate MPEG2 and down convert/shrink later. As I want to do edits etc it would be a re-render and not a requant.
2. Speed up FFV1 support in FFMPEG? Or a suitable replacement.
3. Better/quicker lossless MJPEG support
4. Tweak hard drive performance for better huffy support.
Your Help?
----------
So one and all feed back welcomed, and flames ignored. What are people using and just how fussy are you?
I'm based in NZ so I don't have any DVB-T or DVB-S access to hand, and HW MPEG2 is silly prices (in NZ terms). I want a good analog capture system for off air and VHS conversions.
Cheers
Steve
-------------------------------------------------------
This SF.Net email sponsored by Black Hat Briefings & Training.
Attend Black Hat Briefings & Training, Las Vegas July 24-29 - digital self defense, top technical experts, no vendor pitches, unmatched networking opportunities. Visit www.blackhat.com
_______________________________________________
Mjpeg-users mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/mjpeg-users
