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31

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. ffmpeg is a command line tool, which means that it can be ...


18

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), - ...


8

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 ...


8

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


7

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

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

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 ...


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

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

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

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

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

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

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

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 ...


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 changes bitrate it ...


3

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


3

This is the command line I have used to encode ProRes 4444. If you do not include -bits_per_mb you will get low res results in Windows 10. Many posts do not mention this little aspect. ffmpeg -y -f mov -i input-file.mov -vcodec prores_ks -pix_fmt yuva444p10le -profile:v 4444 -bits_per_mb 8000 -s 1920x1080 output-file.mov


3

I read up a bit and made some experiments with lossless codecs, getting decent results. I'd be interested in comments on this, especially if there are lossless or lossy alternatives that I overlooked. I tried the following codecs / formats in ffmpeg: Lossless Motion JPEG2000 / AVI ffmpeg -i test.avi -vcodec jpeg2000 -strict -2 -pred 1 test_jpeg2000.avi ...


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

The answer is No. Besides the frame dimensions, there's the matter of content complexity. Without scanning the video and doing a first-pass as it were, it's not possible to predict the output size. A video consisting of a slideshow of very simple text slides will be much easier to compress than scenes of busy city life..etc. The closest you may come to ...


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. ...


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