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HDMI Capture Problem SOLVED - AviSynth RULES!

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    Originally posted by LeavingTheCandy View Post
    Wow! What some Voodoo. I was thinking about trying my GH2 to my KiPro, but I think I'll have a beer instead.
    I hope you're not being scared off by all this tech talk. The basic process works extremely well, and is described in detail in the first post of this thread.
    While there is certainly a learning curve, once you get over that hump, the process is completely automatic.

    If you already have a KiPro, it would be a shame not to use it with the GH2.

    Comment


      Hey guys.

      That's pretty disappointing (re. the XDCamHD). I've been accused of pixel peeping many times and this time i see no difference between the proresHQ and the Mpeg, but - OK- i trust your judgement and knowledge on the matter.

      I use the latest setup and snow leopard, et cetera. Still, the DNxHD footage doesn't look even close to the proresHQ Ninja-recorded footage.

      Two questions.

      1)
      Can you give us Mac users all some last and ultimate advise, apart from going the Cineform route, that would provide the best picture quality and replication of the original Ninja footage with FInal Cut Pro?

      2) WHICH version of Cineform - if i want to follow that route - should i obtain and do i need to pay for both a PC license AND a Mac license?

      Feeling the workflow is close to perfection, but the results still looks sh*t on the mac...


      Thanks, Martin.
      Last edited by martinbeek; 05-08-2011, 02:28 PM.

      Comment


        Originally posted by martinbeek View Post
        (re. the XDCamHD). I've been accused of pixel peeping many times and this time i see no difference between the proresHQ and the Mpeg
        Are you saying that rendering to XDCam and then viewing that file on the Mac, looks identical to the original Prores on the PC? Then use it! You've solved the problem!

        Comment


          Originally posted by Ralph B View Post
          Are you saying that rendering to XDCam and then viewing that file on the Mac, looks identical to the original Prores on the PC? Then use it! You've solved the problem!
          Well... what i'm saying is, that I can not see the difference, but then again, i have no calibrated monitor or special measurement equipment to judge the results. I am just confused, just as LeavingTheCandy, by all the tech details regarding RGB.
          If you say that this is all but lossless, i'l take your word for it - no mistake - and i'll dump XDCam right away.

          I will now - as a test - first follow the route mentioned in this article:
          That suggests converting the DNxHD footage to Prores using Compressor; it seems to do a great job in restoring levels and gamma.
          Let you know what i find. If you have suggestions, please let me know.


          Martin.

          Comment


            Originally posted by martinbeek View Post
            Well... what i'm saying is, that I can not see the difference, but then again, i have no calibrated monitor or special measurement equipment to judge the results.

            You don't need any special equipment. Just take a screenshot of the same frame using the same method , and compare in photoshop or a browser

            All that matters is if YOU can see the difference. If you think it's fine , then go ahead and use it ... But I'm telling you - it's not as good as DNxHD, not at those bitrates you're using. It might be "good enough" for whatever you're using it for...

            If you use long GOP MPEG2, you will have fluctuations in frame quality. B-frames will be a lot lower quality. I-frame will provide more consistent interframe quality but you need about 250+ MB/s for similar results as ProRes422 or DNxHD175 .

            This was taken from your examples:
            http://www.mediafire.com/?135ece6dz1esbdg

            Even without zooming you can see the differences. DNxHD does a fairly good job, but the fine detail and grain is gone in the MPEG2 encode, and dark shadow areas are negatively affected. The MPEG2 encode used even higher settings than the settings you were using.

            Remember this was a fairly static scene. If you had more motion or complex content, it would have fallen apart even more. The compression simply isn't good enough at those bitrates. It will certainly be better than the onboard AVCHD @ 24Mb/s, but it's clearly worse than DNxHD in terms of compression



            I am just confused, just as LeavingTheCandy, by all the tech details regarding RGB.
            If you say that this is all but lossless, i'l take your word for it - no mistake - and i'll dump XDCam right away.
            The take home message about RGB is this: You need a format that Mac software will recognize as Y'CbCr , not RGB, otherwise it will clip data and screw up the gamma.

            I suspect DNxHD is probably being clipped by your Mac software as well because it's treated as RGB - I would do some tests with full range (slightly overexposed) subjects

            MPEG2 will work, but you need higher bitrates; 100MB/s isn't enough. I can't find any free encoders that will do this for you (I tried HCEnc, but it's not working properly with 422 or it's crashing on very high bitrates)

            Comment


              The one that works here for quicktime on the PC is uncompressed 2VUY . (When you re-open the exported file in QT it looks the same as the Prores). Theoretically it should work when transferred to Mac as well. Other forms of uncompressed don't seem get treated as uncompressed Y'CbCr, and other compression formats are mishandled even when encoded through quicktime itself.

              Filesize will be about 4-5x larger than the ninja prores, but at least you won't be clipping data, or incurring compression losses. You can convert that to prores on the mac if you want to.

              Add this to the end of the script, and then play the avs in vdub or a media player like MPC to write the file

              ConvertToYUY2()
              QTOutput("out.mov", format="2Vuy", raw="uyvy")

              Comment


                STOP PRESS!!!

                http://www.matrox.com/video/en/support/downloads/

                I just installed the Matrox VFW Software Codecs, and their MPEG2 I-Frame Codec is fabulous at high data rates.
                And they have a version of it that runs on the Mac. We may just have found the ideal cross platform codec.

                I ran it through five generations and it held up so well, that I recommend it without any hestitation.

                The only question I have is, since it renders to an AVI file on the PC, will that be directly readable on a Mac?

                Comment


                  Good idea Ralph!

                  You should be able to re-wrap into mov with ffmpeg

                  ffmpeg -i input.avi -vcodec copy output.mov

                  You can batch re-wrap with a .bat file as well

                  Whether or not FCP "likes" it is another matter... IIRC, some MAC nanoflash users had some problems with high bitrate I-frame MPEG2 files

                  or does the MAC version allow you to parse AVI wrapped MPEG2 ?



                  EDIT: hmm maybe not so good. It forces a RGB conversion, and the decoder output is RGB if you are using matrox decoder...If you use other decoder you can decode in Y'CbCr, but the levels are clipped. I can't find a way to make it pass through Y'CbCr levels untouched, preserving all the data.
                  Last edited by PDR; 05-09-2011, 08:56 PM.

                  Comment


                    HUmmm

                    http://www.matrox.com/video/media/pd..._Codecs_10.pdf


                    check the page 3

                    Comment


                      That setting should work for full range RGB to prevent clipping, but it's output pin is still RGB if you use the matrox decoder

                      Ideally you want Y'CbCr all the way through to avoid Y'CbCr<=>RGB conversions (slight preventable quality loss incurred)

                      Full range RGB won't look like the prores capture, it will look flatter, less contrast

                      Comment


                        Before we draw any conclusions, we need somebody with a Mac to test it and see how the files come across.

                        In any event, this is a helluva good codec, and I'm glad I found it. I'm going to use it in my own work.

                        Comment


                          Problem solved

                          Great news! I've solved the "DNxHD Mac conversion problem"!
                          I've ran the DNxHD file through the freeware utility "MPEG STREAMCLIP", saving it as ProRes444 and the whole signal range is correctly translated to ProRes444 YCbCr and definitely not to RGB.
                          Signal on scopes is now identical to Ninja HDMI recording.
                          Wow!

                          And indeed, DNxHD looks so much better than XDcamHD.

                          A great relieve...


                          Martin

                          Comment


                            Is this necessary also for PAL footage or only applies to NTSC? Can it be done on a Mac?

                            Thanks

                            Comment


                              Originally posted by ChemiX View Post
                              Is this necessary also for PAL footage or only applies to NTSC? Can it be done on a Mac?

                              Thanks
                              If you're shooting 24P through the HDMI with a PAL GH2, then yes, you will need to fix the footage. Avisynth is the best (and perhaps only) way to do this correctly. As you probably know, Avisynth is a Windows program and does not run on a Mac. However, there are several ways to run Windows on a Mac. MartinBeek has successfully implimented an Avisynth workflow on a Mac. I suggest you study his posts in this thread.

                              Comment


                                Hello all, and PDR and RalphB in particular.

                                Since you have proven to have much better eyes (or monitoring) than i, can you please have a look at the resulting footage when doing the conversion "back to mac" using MPEG StreamClip to get all levels and gamma right for use in FCP.

                                The original AviSynth DNxHD clip and the resulting MPEG StreamClip ProRes444 clip can be downloaded here: http://www.megaupload.com/?d=DIF7KJN8 (501 MB)

                                To my eye, levels look OK now in FCP and conversion is very fast.
                                My question to you is, if it is a lossless process and if you can spot any anomalies in either the levels, sharpness or color.

                                Thanks a bunch!

                                Martin Beek

                                Comment

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