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While there are video encoders that do this kind of thing, most commonly this is the work of a video switcher or mixer. A video switcher is a device used for mixing live video from multiple sources. The bad news is they generally aren't cheap. An HD capable switcher is typically in the $6000+ range with the absolute cheapest one I know of being the Black ...


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Complexity is the main thing. Because of how audio works, there tends to not be a whole lot of variation in the quality you get from a given bit rate. While video often has frames that are very similar from one image to another, audio rarely has the exact same sound playing for a long period of time. This lack of predictability in audio means that the ...


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Your best bet for high quality and low size is 2 pass variable bit rate, but it is worth noting that the size of the video also has a ton to do with how much motion it contains and how often the scene changes. One of the most popular modern codecs to use for such compression is h.264. Video compression works by looking for similarities not only within one ...


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Depending how the content was made, the banding might be introduced when you're converting your content from RGB colorspace to YUV. You can try to make an h264 while keeping RGB colorspace, although I've read it's not easy. Are you able to use another codec?


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The bands you're referring to could well just be a limitation of the 8-bit colour space. In theory the way to solve this is to use 10- or 12-bit colour space through every stage from rendering, to editing and mastering, through to output and even in the screen or projector. However your final output is probably going to be displayed in an 8 bits per ...


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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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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 ...


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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. ...


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When you ask how something will 'look' you're in the realm of the subjective. Things 'look' different to experienced professionals than they might to the average viewer. But still, the 1080p video will not be as good no matter what you view it on. When you encode at a low bit rate you aren't removing pixels, you're mostly removing high frequencies. Doing ...


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For CBR encodings, the bitrate is always kept at the bitrate specified regardless of if it is needed. For VBR encoding, the bitrate is an average target, however the media stream will use more or less data rate when it needs to but will try to average to the target. This is why you see 1 pass and 2 pass VBR. 2 pass VBR first makes a pass to estimate where ...


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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 ...


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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 ...


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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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There's a table here showing support for the various video codecs by the four main browsers around today. For Chrome and Safari the only option that plays on both is h.264 in an mp4 container. I've found that main profile h264 video plays best across most modern devices, but you can wind it back to base profile if you're having problems. This is a good ...


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x264 would be a good option, its an extremely fast and efficient h264 encoder, probably the best on the market and its open source. I has several good presets/profiles f.e. the ultrafast profile which can encode FullHD with several 100FPS on a modern multi core cpu. I made good experiences with it regarding capturing real time rendering applications. Its ...


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There is a rule in compression, quality, size and speed, pick two of three. Video compression is an incredibly complex process that requires a lot of resources on either the CPU, GPU or both. You can get around that one of two ways, you can either reduce the level of compression (with lossless being the fullest extreme) or you can reduce the quality ...


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Just to add a bit to AJ Henderson correct answer. You do can compress in a lossless way with h264, this is the lossless predictive profile and is achieved by encoding with a CRF setting of 0. Though while you get lossless h264 compression that way you will endup with a larger file than your source file. Lossy compression cant be done twice without loosing ...


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You have a misunderstanding of how compression works. In all but a few specialized types of lossy compression, when you compress something a second time, even in a much higher quality level than previous encodings, you still lose additional quality. Using a slower encoding from the same original source with constant quality will often produce a smaller ...


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The output is an .MTS file, which is ~450 MB. What is the reason for that? It is desirable to record and master in the highest quality possible, and only convert to lower bitrates for delivery (if necessary) at the final stage. 450MB for two minutes is 30mbps. That's not particularly high for a capture bitrate; it's a typical capture bitrate for ...


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HD video is very, very large at high quality. 450MB for two minutes isn't actually that bad. To put it in perspective, assuming you were shooting 1080P and 24fps, if there was no compression applied, that same 2 minutes of video would be 6 gigabytes of information. The reason that videos you download or watch on bluray disks are so much smaller is that ...


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The first thing I would try is to add -force_key_frames to your original command, drop the preset and lower the -crf value. The following example sets a key frame every second. ffmpg -i input.mov -c:v libx264 -profile main \ -force_key_frames expr:gte(t,n_forced*1) \ -crf 15 -pix_fmt yuv420p -an output.mp4 As a second resort I would use a series ...


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You can see the bitrate in this case as a quality target. It will not encode the audio strictly at that bit-rate but try to encode the audio in a way that it will always be "near" your specified bit-rate. Usually you can translate certain bit-rates to a specific quality level which can be compared to lames "V0", "V2" etc. VBR settings, these presets don't ...


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The best bet is either a slide show player or a variable frame rate video format. Since your image doesn't actually change for large periods of time, formats that normally use a fixed frame rate are not going to produce nearly the quality of results of a VFR format. Handbrake is one option which appears to support using a VFR format.


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I would recommend the h264 codec as it produces reasonable quality at small size and it provides broad compatibility. The open source encoder x264 is considered as the best one out there. I can't recommend any command line parameters but there are several good programs that make use of the x264 encoder. I like Vidcoder which is a fork of the popular ...


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Well the program that encoded the file that works was Apple QuickTime so not much of a suprise that it's working. QuickTime can be a little picky when it comes to mpeg4/h264 encoded files. I looked at the files and possible factors are the encoding profile and maybe the GOP setting. Basline Profile Level 3.0 for the broken one and Main Profile Level 3.1 for ...


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Motion compensation is the use of the motion estimation information to achieve compression. If you can describe the motion, then you only have to describe the changes that occur after compensating for that motion. I used this article as a primer. Basically the first involves how you determine what movement is happening and the other is then used to ...


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So Apparently FFMPEG can do this, I had to use -c:v copy and that will leave the video stream intact. I actually used an app called iFFMPEG to figure this out.


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I know that Virtual Dub can do this, but it only works with a limited number of codecs. Since it's free, it's worth a look to see if it'll do what you want. Otherwise, any demux/remux software will work, but it'll take three steps. First demultiplex the file into video and audio streams, re-encode the audio as needed, then remux them into a combined stream. ...



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