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4

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.


3

You can use the pad video filter to add the required space on the bottom, and then the overlay video filter to place the image: ffmpeg -i video.vob -i image.png -filter_complex \ "[0:v]pad=0:ih+20[bg];[bg][1:v]overlay=0:H-h,format=yuv420p[v]" \ -map "[v]" -map 0:a -c:v libx264 -c:a aac -strict -2 -movflags +faststart output.mp4 I had to make some ...


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I think it is easier to combine a full dimension background image (720x500px) with your video in ffmpeg instead of adding the 20px footer to the video. You can simply use the overlay filter for this: ffmpeg \ -loop 1 -i 720x500.jpg \ -i 720x480.mp4 \ -filter_complex overlay=0:0 \ -t 0:01.48 \ out.m4v Note: In this example you have to ...


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There might not be a way. Based on your description of the problem, it sounds like the processing is the slow part. While the video encoder itself is able to do multi-threaded processing, the image processing you are doing may not be able to. By default, Premiere has always done as much parallel processing as possible for me and I frequently see it hit ...


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To expand on LordNeckbeard's answer, yes, just mux the JPEG data into an MJPEG video stream. That will be the smallest representation of the exact sequence of output images, even though MJPEG is a terribly inefficient codec by today's standards. (no temporal redundancy, and not even any intra prediction. You can make a variable-framerate MJPEG video to ...


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This will output a lossless H.264 video where frames will use information from other frames ffmpeg -f image2 -r 30 -i %09d.jpg -vcodec libx264 -profile:v high444 -refs 16 -crf 0 -preset ultrafast a.mp4 Explanation of options: -f image2 - tells ffmpeg to select a group of images -r 30 - tells ffmpeg to encode at 30 frames (or images) per second (change ...


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I've answered a similar question some time ago. YouTube added a few codecs since then but all the info there still applys: What codec will my Youtube uploads be output in and what codec should I use to upload? Short answer: Yes if you are concerned about maximum quality a lossless codec or visually lossless codec is the way to go. Re-encoding always means ...


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


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If the frame-rate is not too high and you can associate a frame with a precise timestamp then the easiest would be to add the metadata as textual subtitles. The other option is to mux the metadata as standard headers in .mp4 or similar container format. .mp4 can be broken down into multiple fragments, each one with its own header, and theoretically this can ...


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This isn't a phenomenon, this is compression. It is simply how it works. Compression works by taking an input, runs it through some algorithms and then gets an output that matches up either exactly (lossless) or approximately (lossy) with the original input. It is not stored like normal video data as a set of pixels, but rather some form of data that ...


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To understand this you need to understand how codecs actually work. A plain uncompressed video frame e.g. a single picture is pretty large. I'm talking about a bitmap, not a lossless encoded video, no encoding at all, just plain pixel information. Here simple example of a Full HD frame for some perspective: We have a resolution of 1920x1080 that equals to ...


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That is way out of the h264 specs. According to Adobe After Effects the format constrains for h264 are at min. 10fps so even 2fps are (not, see below) out of spec and could result in issues with some players. So Avidemux seems to allow out of spec settings, that 1 fps isn't possible, is very likely an internal issue with how h264 gets encoded in Avidemux. ...


2

It is hard to say without seeing the file itself, but my best guess is that an issue occurred causing the data stream to die but the meta data was still set "properly". Generally, the actual video data itself is not looked at for the length of the video. Instead, there is header meta data in the file that holds the video stream which indicates how long the ...


2

A standard for WAV is 48K / 16 bit mono, or stereo if there's ambiance or presence you'd like to preserve. The last two parameters are a consequence of those choices and you can calculate them based on your selection. Then any compression you might apply afterward will have a good starting basis. If all you're after is intelligibility, a lower sample rate ...


2

No, such a thing does not exist. You can get some very rough guidelines in terms of things like suggested recording profiles for Youtube, Vimeo, or bitrates used by Netflix, Hulu and Amazon Instant Watch, but at the end of the day, the bitrate needed for a given resolution is entirely content dependent as well as dependent on how much time you can spend ...


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In case of H.264 codec, you can use YouTube recommendations. Here's Vimeo video compression guidelines


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It depends a bit on your file format. But it is possible; if you create a title as a separate video you can concatenate (join) the title and the original video usng tools such as ffmpeg. Generally this will work best if they are the same codec with the same settings. For concatenation using ffmpeg see the FAQ. Some formats, like MPEG2 program streams (like ...


2

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.


2

Players buffer streams. The bigger the buffer size, the longer window the encoder has to use higher bitrates for hard content, and then fewer bits earlier or later on easy content, to achieve similar quality for the whole video. I'll assume you're going to use h.264 (aka AVC) as a codec, as it's the de-facto standard for streaming video on the Internet. ...


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Any decent encoder can hit a target bitrate (with 2pass), but still spend the bits intelligently to achieve similar quality throughout the file. x264 2pass figures out what CRF will give the desired bitrate (pass1), and then uses it (pass2). (source: Dark Shikari. cf. the links I dug up for my answer on this question about VBR streaming). You only get ...


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I'm not sure how this fits into a streaming strategy, but the DPX file format includes per-frame metadata (potentially a great deal of it). This Wikipedia article has the basic info. I'm also not clear on what you mean by 'bound permanently'. In the AVI file container the "I" stands for "Interleaved", where video and audio packets (roughly) alternate in the ...


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To elaborate a little further on what Peter says, in general using multiple processors helps in cases where you have several independent tasks that all need to be done but don't have dependencies on each other, or one task where you're performing the same math on massive amounts of data. If, however, you need to the output of calculation A as the input of ...


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The article you linked is not very good. Normally, single pass bitrate encodings convert your bitrate into a RF value with a maximum bitrate limit and takes it from there. x264's one-pass ABR ratecontrol is not implemented as CRF + limit. He's right that 2pass is by far the best way to hit a target bitrate, though. And he apparently doesn't ...


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Because 4096 / 1920 = 2.13333 and 2160/1080 = 2. They are different aspect ratios, so yes, they end up letter boxing when you convert between them. That is the expected result. The 4K format you are using is a multiple of 2K and is not the same widescreen aspect ratio as 1080p. You can't translate between them without letterboxing, though there are ...


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Probably no loss, but there is more to it than just YUV420. You can need to make sure the same ITU-R Recommendation is used (BT.601, BT.708 or maybe even 2020) In addition make sure the same color ranges is used (0-255 vs 16-235)


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You're right, at some point it visually looks better to downscale and have a lower rez but less artifacty video. The bitrate where this happens depends strongly on how compressible your content is. One way to judge this for x264 might be to look at the rate-factor. For 2-pass, the x264 output includes the rate-factor. For CRF mode, the CRF value you set ...


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It looks like the x265 codec needs to be installed for the App you are using to play the file with. VLC does support x265 with a dd on codec but it seems the link on there site is broken https://www.videolan.org/developers/x265.html which is not very useful right now. there are some other players out there doing a quick Google brought up some results but I ...


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I assume you record video game footage? Recording and rendering on one machine is something I wouldn't recommend with a regular PC if you play modern games that take a lot of your CPU and GPU resources. I usually recommend getting an SSD but in this case it seems you are heavily CPU limited. You could theoretically encode on the GPU but I'm not sure if that ...


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I doubt it is memory or page fault related. Encoding is more of a stream operation, you load a frame, process the frame, hold the frame until you finish a group of pictures and then encode the group of pictures. It is not a memory intensive process unless you are doing fancy effects that require memory to process. It is a potentially HDD stream intensive ...


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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 ...



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