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5

Well going by the numbers h264 has a lesser bit-depth and color accuracy than ProRes 422. PR422 has 10bit and 4:2:2 chroma sub-sampling, h264 has 8bit and 4:2:0 unless you encode in the Hi422P Intra profile which isn't very well supported in the wild but offers 10bit and 4:2:2. So in that case I don't think you will have any difference what so ever between ...


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Ffmpeg can encode video using ProRes, and runs cross-platform ffmpeg -i input.avi -c:v prores -profile:v 3 -c:a pcm_s16le output.mov will do the trick.


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On Windows, I recommend FootageStudio 4K. It is a commercial converter (not cheap) that supports many professional formats, including ProRes.


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Does youtube store different video files for different bit rate? Yes is the technique called "resampling" ? No Does youtube make live resampling for every user ? No All this things happens live ? No, not on youtube. But Yes on twitch.tv Or it encode and save different video files for different bitrate, so that when a user ...


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There was one, but it fell in to disuse and isn't used very often anymore, largely because of the lack of mobile support, but also due to security issues it created. It was called Flash.


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The original AppleTV could only playback at 1280x720 at 24fps. Because your video is at 25fps, it has to use a slightly lower resolution. If you either lower the frame rate (probably not an option) or exclude the original AppleTV, it should export at the higher resolution. I believe there's another setting than the "Most Compatible" one which excludes the ...


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The video may look choppy because of the codec you're using. For fun, I recommend trying out your h.264 variant, x264vfw. I know that h.264 is almost ubiquitously used for internet content. Playback in premiere is extremely variable when it comes to sequence settings, video preview settings, system preferences (such as scratch discs, and optimizing for ...


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H.263 was a sole development of the ITU but I wouldn't bother all too much with the specified use case of video conferencing. It's a codec with the main purpose of improving the compression compared to older codecs which of course is beneficial for video conferencing where bandwidth is a very limiting factor, especially at the time the codec got developed. ...


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Try to extract header from other file (e.g. create a new one with that recording software) and prepend it to your stream. On Windows you can use that command to concatenate files: copy /b header.hdr + stream.mov outputFile.mov


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The University of Bath released a paper demonstrating a vector-based video codec a couple of years ago, with a press release asking "is the pixel about to die?". Strangely since then the pixel hasn't died, in fact there are even more of them around than there used to be. You could argue that most video codecs do actually use vectors: DCT (or similar), - ...


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Has anyone done or seen any tests comparing Apple ProRes 422 with high-bitrate H.264? No, but I can tell you that x264 can get as close to lossless as you want (or even mathematically lossless, with -qp 0). x264 can produce h.264 streams in 4:2:0, 4:2:2, or 4:4:4 YUV colorspaces, at 8 or 10 bits per component. (It can also do RGB, but unless you're ...


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I've tried a bunch of front ends for ffmpeg and finally settled on Tencoder. Widows only. It has a preset for ProRes and is very easy to customize so you can crete setting for often used formats or settings. It is multithreaded and allows you to do batch processing.


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What is Ogg Skeleton? From Ogg Skeleton 4: Ogg Skeleton provides structuring information for multitrack Ogg files. It is compatible with Ogg Theora and provides extra clues for synchronization and content negotiation such as language selection. The latest version of Skeleton, version 4.0, also provides keyframe indexes to enable optimal seeking ...


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You can try ffmbc - a customized version of FFmpeg. Unfortunately there are no builds for linux or windows at the moment so you have compile it yourself.


1

After reviewing the PDF, I can confirm that you are misreading it. They are looking for a flash animation, not a video. You will not be able to use your After Effects assets at all. You need to remake the ad as a flash animation in Adobe Flash using vector graphics in order to fit within their 50KB limitation.


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There isn't a perfect answer to this problem. AVI and MP4 are just container's for video streams, so without knowing more about the actual streams in the containers, it is impossible to tell how much quality loss there would be, but as a general rule of thumb, it isn't all that atypical for AVI to use far less efficient video compression algorithms than MP4 ...


1

Just to add a little bit more info to SlimSCSI's straight up answer. Does youtube store different video files for different bit rate? Yes and no, for the 1080p stream YouTube utilizes a technique called DASH. This serves essentially a video that was encoded with several different bitrates (though its one file) and adapts the bitrate on the fly ...


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The Wikipedia article on MPEG-4 is a great start as the MP4 file specification is part of the MPEG-4 spec. Specifically version 2 of MP4 is MPEG-4 Part 14. While not free, you can purchase copies of the ISO spec under ISO# 14496-14:2003. A preview with some detail is available from the ISO here. It is designed to contain any of the various MPEG video ...


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According to Miraizon support this is a peculiarity in Premiere Pro handling of ProRes that causes it to interact "very inefficiently" with the the codec. There is an update forthcoming but until then they suggested this as a work-around: Move the AppleProResDecoder.qtx from the /Quicktime/QTSystem/ folder to a temp folder. I still get some inconsistencies ...


1

There isn't really an alternative to x264vfw. Are you sure the error is with the codec and not your application? It's in wide use, such a major bug would definitely be found. Also be aware that h264 doesn't work in a frame by frame basis unless you encode only intra frames. VP80 is NOT h264, just a similar codec. If you need to develop an app you probably ...


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You don't need a 64bit codec to use it in 64bit Software like VirtualDub or After Effects, a 32bit codec will work just fine. For intermediate codecs I generally use either a QuickTime with PhotoJPEG compression or Animation like you suggested yourself. The latter is lossless and produces fairly big files, the former is lossy just like JPEG but offers ...


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There are no such tools to my knowledge. You will probably have to make these headers yourself. Usually you don't have all that much parameters to set in a format header. If all the streams have the same origin you will be able to use the same header for all streams. Just look into the format specification and edit a sample header in a way it could fit your ...


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h.264 + aac in .mp4. Google up an x264 settings guide. (or use -preset slower). If you're doing something that the MPEG-LA would charge patent royalties for, screw them and use VP8 or VP9, with maybe a fallback to Theora if that helps compat. Old question, but check the quality at the start of the video if using x264. If it's not good, use 2-pass. I ...


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Not all video formats use square pixels. In this case, the pixel's are oval (anamorphic wide screen). This comes indirectly from the film days when anamorphic lenses would condense a wide screen image on to a narrower strip of film. The same concept was later applied to squeeze wide screen videos in to video formats that wouldn't normally support them. ...


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Lossless requires such high bitrates that I have more trouble playing back lossless video than 5Mib/s lossy h.264, on my C2Duo (first gen) E6600, 2.4GHz. lossy 5Mib/s 1080p h.264 at 24fps plays perfectly without even having to use mplayer's -lavdopts threads=2 option. (single-threaded software decoding is enough.) My system isn't fast enough to play ...



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