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  1. Member
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    I'm nearly certain that this question has been asked before, but I couldn't find an adequate answer in short order.

    I'm looking for a way to archive 1080p ProRes 422 files to a format with smaller file sizes without sacrificing.

    ProRes is engineered to strike a balance between compression, which is processor intensive to play, and performance. Too much compression, and the CPU/GPU has to work too hard for the media to be usable on most editing timelines. Compress too little, and the files are too large to efficiently store.

    So, what I'm looking for is a codec that gets the smallest possible file size without compromising quality. These clips will not be used for editing; they would be re-transcoded/inflated to something like mxf or ProRes for editing purposes. However, for the purpose of being compacted into archival storage and subsequently uploaded to the cloud, I want to know what would be the best available format.

    As an analogy, I believe it to be something similar to the difference between WAV and FLAC files. FLAC is considered a lossless format just as WAV is, but FLAC is more processor intensive to decode and play. It's less desirable as an editing format for this reason.

    I guess I'm looking for the FLAC of video codecs, and/or any applicable settings for optimal results.
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  2. 10bit 422 x264 with low crf and maybe --tune grain or similar. But it's not lossless. There is no codec to further compress an already compressed format like ProRes significantly further. WAV to FLAC is different because WAV is uncompressed (well, PCM in WAV is).
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  3. Originally Posted by omarohara View Post
    As an analogy, I believe it to be something similar to the difference between WAV and FLAC files. FLAC is considered a lossless format just as WAV is, but FLAC is more processor intensive to decode and play. It's less desirable as an editing format for this reason.

    I guess I'm looking for the FLAC of video codecs, and/or any applicable settings for optimal results.
    Your comparison to WAV and FLAC is incorrect. A better comparison would be high bitrate MP3 (or MP2, AC3, whatever lossy audio codec) to FLAC. MP3 files would be decompressed to PCM (getting much bigger), then the PCM data is compressed with FLAC. The end result will be bigger than the MP3 source.

    Yes, there are lossless video codecs. But your ProRes files have to be decompressed to uncompressed frames, then those frames are encoded with the lossless codec. The results will be bigger than your ProRes files in most cases because lossless codecs compression less than ProRes. There is an exception: If your sources have large parts of the picture that are exactly the same from frame to frame (often the case with computer graphics) a lossless inter-frame codec may be able to shrink them more than ProRes.

    Note that the final stage of compression with lossy codecs is entropy encoding -- lossless compression of the data after their other forms of compression (DCT, wavelet, etc.). So lossless compression (ie ZIP, RAR, etc.) of the video file doesn't get you any more compression.
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  4. You could approach this the other way, if ProRes is too big for your uploads, then consider what bitrates are alright, you gotta make a decision of some sort, that is why you do all of this. Now you know that lossless or even almost lossless is not a way to make a progress for what you want. There must be an average bitrate ballpark you decide to upload. say 80Mbit/s. So encode as sneaker suggested, encode H264 and limit buffers , a tiny bit more because you would use CRF, using something like:
    x264.10bit.exe --crf 15 --tune grain --keyint 60 --output-csp i422 --vbv-maxrate 75000 --vbv-bufsize 75000

    encode a typical video you do, about 20 min, check bitrates in bitrateviewer , analyze it and decide if those bitrates peaks are ok, if cut off's are happening too often (encoder would distribute even more bitrate) or not at all , then you are more comfortable, you can use even lower CRF or change those buffer limits in command line, you know sort of realize where you are, what quality gives you what bitrate.
    Last edited by _Al_; 11th Feb 2017 at 14:05.
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  5. Originally Posted by _Al_ View Post
    encode H264 and limit buffers , a tiny bit more because you would use CRF, using something like:
    x264.10bit.exe --crf 15 --tune grain --keyint 60 --output-csp i422 --vbv-maxrate 75000 --vbv-bufsize 75000

    encode a typical video you do, about 20 min, check bitrates in bitrateviewer , analyze it and decide if those bitrates peaks are ok, if cut off's are happening too often
    Why should he set buffer limits for archival? What should he even be looking for when deciding if "peaks are ok"? What makes a peak ok/not ok?
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  6. Peaks are not ok if he can see they are cut off in general, but ....

    He does not have to set limits to orient himself, setting buffers to 150000 whatever, especially while testing this, but he has to make a decision what bitrates he is going to upload and what CRF quality gives him what bitrates. He encodes because of volume. He needs to find himself first, he does not know that we cannot tell him what settings give him what quality.

    If bitrates are cut off at their peaks, that is usually in practical point of view, not a problem if CRF is much , muchj lower, problem is encoding with not enough low CRF for problematic parts in video, low light, noise, gradients (10 bit eliminates it sure). In my practical point of view, experience, it is much, much better to lower CRF, set it lower than he would and just limit buffers. Those high peaks are usually more than enough especially because he lowered CRF in the first place. You and I know encoders, how they work, how x264 works. That is what I am talking about , he can use much smaller CRF to boost bitrates for those scenes because he needs to keep many more details for those scenes especially he is going to encode it again.
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