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33

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 ...


30

As of December 2018, Adobe Creative Cloud aps, such as Premier, After Effects and Adobe Media Encoder give you the ability to encode in ProRes without any post-hoc conversion. If you don't use Adobe CC aps or want a free, open source tool, ffmpeg can encode video using ProRes, and runs cross-platform. This ffmpeg command: ffmpeg -i input.avi -c:v ...


15

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.


8

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), - ...


7

There's a single decoder/encoder which reads/converts to both DNxHD and DNxHR. You have to set the correct profile switch. Available options are dnxhd E..V.... dnxhr_444 E..V.... dnxhr_hqx E..V.... dnxhr_hq E..V.... dnxhr_sq E..V.... dnxhr_lb ...


6

You're on the right track with -crf and x264 (the best 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 ...


6

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 ...


6

SVG supports animation using JavaScript and the animate element. That means using a browser or embeddable renderer like WebKit to render it, though. Older games often used their own vector animation formats. You might look into the asset formats supported by open source implementations of old game engines like ScummVM and Sarien. There are some asset ...


6

This issue was fixed with commit 955b818: commit 955b818cf947473ec94a3fe8aa7f408b119fbbc9 Author: Clément Bœsch <clement@stupeflix.com> Date: Thu Sep 1 16:48:45 2016 +0200 ffmpeg: switch to codecpar You can suppress the warning on older version like so: ffmpeg -i Miaow-02-Hidden.m4a -c copy -flags global_header outfile.m4a Example


5

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.


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

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 ...


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

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 doing ...


5

To overlay a half-sized version of a video in the center of an image, use ffmpeg -loop 1 -i image -i video -filter_complex "[1]scale=iw/2:-1[ovrl]; [0][ovrl]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:shortest=1[v]" -map "[v]" -map 1:a -c:v libx264 -c:a copy output.mp4 To frame the video: ffmpeg -loop 1 -i image -i video loop 1 -i ...


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 ...


4

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 support ...


4

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.


4

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


4

I think HE-AAC fits that bill. High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio defined as an MPEG-4 Audio profile in ISO/IEC 14496-3. It is an extension of Low Complexity AAC (AAC LC) optimized for low-bitrate applications such as streaming audio. HE-AAC version 1 profile (HE-AAC ...


4

Both files that don't play feature Opus as the audio codec. As per this site, Opus is not one of the supported audio codecs. Transcode the audio: ffmpeg -i in.mkv -c:v copy out.mkv


4

One of the earliest articles in the IEEE database that uses the term, defines it as "coders and decoders." However, newer material does not seem to be consistent. One of the Wikipedia page's sources (at the time a page author retrieved it) alludes to both encoder-decoder and compression-decompression. This book defines it as compression/decompression.


4

MPEG-4 is not a container specification. It's a suite of specifications. Parts 12 and 14 define containers (MP4). Part 2 defines a video codec, whose encoder implementations are DivX and Xvid. Part 10 defines another video codec AVC a.k.a. H.264. You can get a list of codecs, which can theoretically be present in a MP4 at http://mp4ra.org/codecs.html ...


4

The usual solution for this situation: -fflags +genpts It should eliminate the warning, but there's no guarantee your sync issues will be solved.


4

No, officially, ProRes is not a registered codec for the ISOBMFF family, of which MP4 is a member.


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

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

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 ...


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