VideoHelp Forum

Try DVDFab and download streaming video, copy, convert or make Blu-rays,DVDs! Download free trial !
+ Reply to Thread
Results 1 to 10 of 10
Thread
  1. Member vhelp's Avatar
    Join Date
    Mar 2001
    Location
    New York
    Search Comp PM
    Hi, is there a way to remove the perception benefits in the encoding parameter(s) of these encoders ?

    What parameters do I need to exclude or to include the -no-xyz parts?

    I am not looking to reduce filesize, but rather to retain all video details. I am trying to retain original image details in some test of analog captures and I can't seem to retain all the details unless i encode lossless or near lossless. And that defeats the purpose. For these tests clips, I am not concerned with perception benefits. Thank you in advanced.
    Quote Quote  
  2. Originally Posted by vhelp View Post
    Hi, is there a way to remove the perception benefits in the encoding parameter(s) of these encoders ?

    What parameters do I need to exclude or to include the -no-xyz parts?

    I am not looking to reduce filesize, but rather to retain all video details. I am trying to retain original image details in some test of analog captures and I can't seem to retain all the details unless i encode lossless or near lossless. And that defeats the purpose. For these tests clips, I am not concerned with perception benefits. Thank you in advanced.

    Can you clarify what you mean by "perception" ?

    Did you mean psycho-visual options ? If so, it's actually counter productive for what you want, you need much higher bitrates to retain fine details like fine grain and noise patterns when disabling or using lower strength psy options .

    If you truly want to assess original image details, there is no option but to encode lossless, and that automatically disables psy options
    Quote Quote  
  3. Member vhelp's Avatar
    Join Date
    Mar 2001
    Location
    New York
    Search Comp PM
    psycho-visual
    Yes, I believe that is what it is referred to as. I am trying to retain all the 'noise pattern' that I am seeing in some clips I recently captured but I can't seem to retain any of it. The noise is completely smooth'ed out.

    If I start from scratch, say, at a base starting point, {x264/x265 --preset slow --tune grain -q 20 } what parameters do I need to add to experiment with from this point on, to get me more detail ?
    Quote Quote  
  4. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
    Search PM
    A crf below 18 should be visually lossless.
    Quote Quote  
  5. x264 and ffmpeg now support actually lossless. I think it is different from normal lossy mode in some way - similar to Lossless JPEG.

    https://trac.ffmpeg.org/wiki/Encode/H.264#LosslessH.264
    Lossless H.264

    You can use -qp 0 or -crf 0 to encode a lossless output. Use of -qp is recommended over -crf for lossless because 8-bit and 10-bit x264 use different -crf values for lossless. Two useful presets for this are ultrafast or veryslow since either a fast encoding speed or best compression are usually the most important factors. Most non-FFmpeg based players will not be able to decode lossless (but YouTube can), so if compatibility is an issue you should not use lossless.
    Quote Quote  
  6. Dinosaur Supervisor KarMa's Avatar
    Join Date
    Jul 2015
    Location
    US
    Search Comp PM
    Would stay away from x265 if you want grain retention on VHS tapes, even x264 tune grain. Also HEVC is geared more toward compressing HD and above resolutions which can use up to 64x64 macroblocks. On grainy VHS resolutions the advantages are not as obvious.

    While it might not be recommended, I capture VHS tapes with x264(YUY2) with the faster presets and a CRF of 10-15. x264 supports mbaff interlacing, while I don't think the HEVC standard supports any interlacing. My method is not lossless but sure cuts down on the size and is better than the MPEG2 encoder built in my tuner card.

    Are you deinterlacing your clips? As that kills much of the noise anyway. Some even use QTGMC in progessive mode just to denoise their stuff, including me.
    Quote Quote  
  7. I don't think it will help you, but to disable psycho-visual options use "--no-psy".
    Quote Quote  
  8. Member vhelp's Avatar
    Join Date
    Mar 2001
    Location
    New York
    Search Comp PM
    I figured out the problems that I was having that was giving me poor quality, detail-less videos. The vcr, Image filtering and poor capture equipment. This time, I changed to a different vcr model and a different capture card. That changed everything. I am now getting the details in my videos.

    x264 retains all the detail in my captured videos from vhs, at 12 fps. I wish it could go faster or real-time at least.

    Code:
    x264.exe --preset slow  --tune grain  --crf 18 --output "video.mkv"  "movie.avs"
    But as for x265, I can't seem to get any detail even when using --tune grain. The videos look chalky, especially in dark areas where its easier to look for image details.

    Code:
    avs4x265 -P | x265 --crf 18 --preset slow --frames 3740 --rdoq-level 1 --min-keyint 23 --keyint 240 --aq-mode 2 --profile main10 --level-idc 4 --deblock -3:-3 --tune grain --psy-rd 0.5
    But waiting for the x265 encode to complete is drooling-ly too long. 30 minutes or more for 1 minute clip to encode at 2.28 fps. I'm growing more and more out of patience waiting for every test encode to complete. There's just no room left to speed that software up. Its maxed out. And no i7-xyz is going to encode any faster than that, maybe 4 fps. I think we may be better off using Intel's hardware encoder after all. And I think I'm gonna go for that laptop that was suggested to me in another topic and take my chances. Anyway. I can't find any other way to get "detail" out of x265. But I'm still open to suggestion to try them while I still have some color in my hair. Thanks.
    Quote Quote  
  9. Dinosaur Supervisor KarMa's Avatar
    Join Date
    Jul 2015
    Location
    US
    Search Comp PM
    Originally Posted by vhelp View Post
    I figured out the problems that I was having that was giving me poor quality, detail-less videos. The vcr, Image filtering and poor capture equipment. This time, I changed to a different vcr model and a different capture card. That changed everything. I am now getting the details in my videos.

    x264 retains all the detail in my captured videos from vhs, at 12 fps. I wish it could go faster or real-time at least.
    I'm going to assume you are capturing your tapes losslessly and are then encoding those with x264 after the fact. Which begs the question of what kind of side by side comparison you did with your lossless capture and the x264 encoding. Or did you just not look at the lossless capture and only look at the x264 encoding, and then assumed the problem started with x264. Now knowing that your problem was equipment based and looking at your first post, leads me to think you did not look at the capture.

    Brings up questions about your other thread too. https://forum.videohelp.com/threads/380754-x265-parameters-to-retain-image-grain
    Last edited by KarMa; 7th Nov 2016 at 00:56.
    Quote Quote  
  10. Member
    Join Date
    Aug 2013
    Location
    Central Germany
    Search PM
    Code:
    avs4x265 -P | x265
    Why this pipe? Why -P at all? If your x265 encoder is named "x265.exe", omit it all (-P is only required if your encoder EXE has a different name). Just use x265 parameters for avs4x265 instead. And the last parameter must be the name of your AviSynth script.
    Quote Quote  



Similar Threads