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3

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.


3

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 ...


3

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 ...


3

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 ...


2

http://www.openthefile.com/ext/mjp/4458 and http://www.fileinfo.com/extension/mjp both suggest mplayerx (http://mplayerx.org/) can play them. It would make sense to post a file for people to examine. If mplayer or ffmpeg can play them, chances are mencoder or ffmpeg can encode to the format.


2

If compatibility is your top priority, then you should include two alternative versions of your video on your website, like in this HTML example. As for the exact formats I would suggest: H.264 and AAC in MP4: Chrome, Firefox 22+ on Windows, IE9, Safari 3.1 VP8 and Vorbis in WebM: Firefox fallback for Mac and older versions on Windows. (If you need ...


2

Vantolinomo - You might just be experiencing 'gamma shift' which can happen when you are exporting to H264 video. You can find a tutorial to fix this here: http://www.videocopilot.net/blog/2008/06/fix-quicktime-gamma-shift/


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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. ...


2

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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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 ...


2

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), - ...


1

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 ...


1

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 ...


1

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 ...


1

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 ...


1

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 ...


1

I'm going to repost a section of my answer from this question, as it seems generally relevant: YouTube (as well as Vimeo, and practically every other video website nowadays) works using the H.264 codec. Here are YouTube's instructions for how they'd like videos to be encoded for upload. The TL;DR version of that page: Container: ...


1

This is just a result of the compression that Youtube chooses to apply. Your initial data rate for the video (3.5 megabits for an SD video) is exceptionally high and not really designed for streaming. Youtube probably sees that it is only an SD stream and then drops the bit-rate accordingly. It may not be possible to get better quality since Youtube's ...


1

There's a table here showing support for the various video codecs by the four main browsers around today. For Chrome and Safari the only option that plays on both is h.264 in an mp4 container. I've found that main profile h264 video plays best across most modern devices, but you can wind it back to base profile if you're having problems. This is a good ...


1

I resolved this issue by installing VLC. Apparently VLC has some necessary codecs that Vegas Pro uses. After installing VLC I was able to import the video and use it normally with no hindrances.


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You can try using either of the two Motion JPEG codec's available with Quicktime and see if either of those works after renaming the extension. Motion JPEGs are kind of a major pain though because it's literally just a sequence of JPEG images for each frame within the video and the exact specifications of the container can vary. This can result in files ...


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Not sure on the AVI but kept searching and found http://sketchucation.com/forums/viewtopic.php?f=11&t=18827 What OS are you using? Vista 64 bit has codec issues, so if it is indeed a Vista 64 bit you need to export as a series of images (which is best anyway) and compile it in after effects. I'm on Windows 7 so don't know why it was an issue ...


1

I don't know about the specific format of mjpeg that you are working with, but it is certainly possible to handle interlaced video with mjpeg. I believe the most common way is to do a jpeg per field, so you get half the vertical resolution and alternate between the odd and even fields.


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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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