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12

Some general info about the formats used: YouTube uses 4 container formats and 3 diffrent codecs. It depends on the popularity of the video what codecs are used for your video (see below why). Generally, every of your uploaded video will be encoded in h.264 and will be muxed into an .flv and .mp4 container. Thats the standard and this will hapen for every ...


5

There's a philosophical difference between delivery codecs (e.g. mpeg4, avchd), editing codecs (e.g. DNxHD, ProRes, Cineform), and capture codecs (e.g. r3d, DVCPROHD). While almost any codec can be used for each of these three stages, your workflow needs will help you decide which are best suited for each stage. The question you seem to be asking, is ...


5

What you are describing is effectively what 2-pass VBR does for you. It makes a first path that calculates the level of change for each particular time in the video and then uses this information to make the best possible use of the available storage space. It is, however, entirely possible to do the process manually by doing multiple encodings with ...


4

Personally I always choose MP4 container and the H.264 codec as this is also the codec YouTube uses in the final video stream. What key-frame rates and compression you need really depends on the footage and it's unfortunately close to impossible to give as a generic answer for this reason. If you have a lot of movements you will need key-frames more often ...


4

The .mpg and .mpeg extensions are typically associated with MPEG-1 and MPEG-2 files. The structure of these files is different than the .mp4 format used for H.264 video, part of the MPEG-4 family of formats. I suspect VLC and WMP can play the file because they must not be using the file extension to determine file type, they probably parse the file with all ...


4

That looks more like a 'field' from the video, rather than a frame -- jagged diagonals are the tell. If your video is interlaced, you may only get half the vertical resolution in a still, unless you specifically set it to output a full frame. Check the export settings.


3

What format YT output their video depends on various factors. For most ordinary videos they use H264 encoded streams for video (AAC or MP3 for audio) in form of MP4 and FLV container files. These are just containers holding the encoded video data - although the H264-encoded format is no guarantee with FLV-files (or in theory with MP4 files) as they can also ...


3

You're on the right track with -crf and x264 (the H.264 encoder), and it should provide the "quality threshold" that you're looking for. CRF is recommended if you want a certain output quality and output file size is of less importance. Conversely, performing a two-pass encode with -b:v is recommend if you are targeting a specific output file size and ...


3

1) If you're not going to deinterlace it then stick to the source's field order. 2) I wouldn't bother with the two pass encoding (if indeed it even does anything) - dnxhd will only encode at certain specific fixed bit rates anyway so you're actually pretty constrained for options. 3) You'll see some softening, but it's unavoidable. ffmbc's filtering is ok ...


3

For a server, you definitely want ffmpeg. I would also strongly recommend compiling it yourself (those are Ubuntu instructions, but should work for Debian as well AFAIK) - the best AAC encoder available for ffmpeg (libfdk_aac) cannot be redistributed alongside x264 (because of the GPL), and the version of ffmpeg in the repositories is probably too old for ...


3

I'll start by pointing you to another answer I wrote before, roughly covering the different kinds of codecs. (Nice edit on your question, by the way, removing the file size limitation helped figure out what you were after.) My recommendation (again) will be to either use ProRes 422 or Cineform as your intermediate, probably via Magic Bullet Grinder or ...


3

I don't know what tags or fields are present in a .MP4 file, but something is flagging the file as having a 16:9 'display aspect ratio' (shown as "dar" in GSpot), while the 'pixel aspect ratio' (par) is 4:3. ((480 * 16) / 9) = 853


3

DV has a something of a focus on simplicity, so it can be encoded with primitive microprocessors and decoded quickly in an NLE. In particular, it's intra-frame: a DV file is basically an array of still-image files. That's useful for professional editing; it means however DV can't achieve nearly as high compression ratios as more complicated formats with P- ...


3

First we need a primer on I, P and B frames. An I frame is a frame that is a completely independant picture of the frame. It doesn't depend on any other frames and is a frame which B and P frames are based on. A P frame stores only the changes from the previous frame and a B frame stores only the changes in either direction. IPB uses a mix of all 3 frame ...


3

Many different factors can contribute to stutter in video playback. It could be a CPU issue (check your CPU when playing the video) in which case, a simpler codec or a player that can leverage the graphics card for decoding would help. It could also be data rate related though. In this case, using a simpler format would actually compound the problem as ...


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 ...


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 ...


2

Let me describe what the bottleneck in seeking is. You didn't say what format are your videos encoded in, but I'm guessing you are using H.264 or maybe MPEG-2. Am I correct? To maximize quality, these codecs have different compression formats, and each frame gets encoded differently. This is a brief summary of the compression types: I-frames (I stands ...


2

Fixed by updating FFMpeg to newer version


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In many instances you can use ffmpeg to create a clip out of a longer clip, and request that the original frames are copied instead of re-encoded. I'm writing this from memory so you may want to double check, but I believe the command line options you need to use for this are: ffmpeg -i <source-filename> -vcodec copy -acodec copy -ss ...


2

Codecs are algorithms, so as such they are completely independent of a programming language. That said, there are plenty of open source codecs implemented in C that you can learn from. For example, take a look at the libavcodec library which has a large variety of codecs, some very complex, and some not so much. I believe to make sense of the code you ...


2

I installed Sony Vegas Movie Studio HD ($34). The download took half a minute, the same to install it, no prerequisities ( except the software updated windows installer ) and everything worked and has been working like a charm.


2

Targa (TGA in the format options menu in AE) is a lossless codec that works with video (most people who know it know it from early days of image compression). It has better file compression ratios than Animation, but retains alpha support (32b/p). Its main advantage is that it's faster than animation. PNG (as used in pictures on the internet) also supports ...


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/


2

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

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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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 ...


1

Ut Video is an editor friendly lossless video codec and is a good choice for in house production as an intermediary. It is fast, open source, actively developed, supports RGB(A)/ULRA (for your alpha channel requirement) and YUV colorspaces, and is available for Windows, OS X, and Linux. You can install it on Windows and it will show up in Adobe Media ...



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