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20

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


9

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 ...


6

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.


5

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 ...


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 ...


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 ...


5

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.


4

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 ...


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

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 ...


4

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 ...


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.


4

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

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

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

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

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 ...


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 ...


3

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 ...


3

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 ...


3

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


3

MPEG -TS. See here: All MPEG-2 TS operations from GPAC (client and MP42TS) are supported on HEVC. MP42TS can be used to generate TS files usable for DASH or for injection in modulation chains; it can also be used to send the TS over an UDP or RTP stream in unicast or multicast mode


3

I haven't used VLC as my primary player since 2007. I switched over initially to KMPlayer and then Potplayer. Potplayer allows fairly flexible splitter and codec assignment for decoding. It also sports a whole host of video and audio processing filters. In fact, I believe that one can use Avisynth filters to process the video during playback, too.


3

While I always guessed that the big / little endian was more a matter of patents rather than performance, Nope little endian was developed as a performance optimization whern moving to multi byte words. https://en.wikipedia.org/wiki/Endianness#Optimization Nothing to to with patents. Different representation have different advantages and disadvantage. ...


3

The order of the components in RGB32 seems to do with endianness: PIX_FMT_RGB32 is handled in an endian-specific manner. An RGBA color is put together as: (A << 24) | (R << 16) | (G << 8) | B This is stored as BGRA on little-endian CPU architectures and ARGB on big-endian CPUs. The descriptions of the various related formats ...


3

Use this ffmpeg* command: ffmpeg -i "20151105-175532.dad" -c:v copy "20151105-175532.mp4" *get 32-bit static build.


2

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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