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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

I have a large set of jpgs that I want to convert to a video losslessly You can probably just mux the jpg images: ffmpeg -r 30 -i input%03d.jpg -codec copy output.mkv Then compare the md5sums of each frame with the framemd5 muxer: $ ffmpeg -i input%03d.jpg -f framemd5 - 0, 0, 0, 1, 460800, 29bcc2db3726c7dfec1826c5740f603f ...


4

I'm not sure how it will behave at very low frame rates, but it is worth pointing out this would also limit your options on how and when you could change frames since they would have to follow on the clock cycles. What is more likely to work in this case is a long keyframe interval. The majority of frames in a compression like H.264 only store the changes ...


3

It looks like a problem with the playback engine. I would try updating your video card drivers and/or making sure the playback engine (in the project/ project settings/general menu) is set to Mercury Playback Engine Software Only. If that doesn't work, I'd try uninstalling and re-installing Premiere. I don't know what can cause it on Mac OS, but on ...


3

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 ...


2

If you are willing to use Adobe products, Premiere supports direct integration with Adobe Media Encoder and can be set with presets that include multiple output formats and sizes. Each encoding runs off the actual main project, thus you remove the extra generation of loss. Alternately, using a lossless quality intermediate file will prevent issues as no ...


2

Unfortunately you are not going to be able to accomplish your goal. Two major factors impact this. First, color processing on different systems is going to differ. This will result in slight differences in the colors that are displayed because many video players apply "enhancements" to video and what you actually see when viewing the video in a browser is ...


2

I'm with AJ. Unless you know the characteristics of every player that might view this, it would be unwise to rely on a small sample of test results. Using a standard frame rate like 24 fps with a keyframe interval of 24 frames will give you essentially the same thing with no compromise in compatibility. The intermediate frames will be minimally small because ...


2

10 times the length does sound pretty long, but isn't completely insane, particularly if you are running two pass. The more compression you are trying to do while maintaining quality, the longer it is going to take to compress it down. It's also possible that if you are using nested projects, it may still be trying to do some rendering at the native ...


2

I'm sure there are dedicated MP4 encoders out there, maybe someone else has better info. But I've had good results using AVC Ultimate, which takes advantage of CUDA on an NVIDIA card to speed up MP4 processing, to about double the rate I get without it. There's a free version, but I can't remember if the CUDA option is available in that -- I've used the ...


2

There are many hardware options including Intel media SDK, FPGA options, nvidi, ASIC solutions, elgato, etc. But for my money, I prefer quality. The software solutions, especially x264, perform WAY (WAY) better as measured by visual quality by file size ratio. As for Quality per watt in terms of encoding, you cant beat a good ASIC.


2

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 ...


2

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 ...


2

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 ...


2

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 ...


2

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?


2

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 ...


2

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 ...


2

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

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 ...


2

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 ...


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

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 ...


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 ...


1

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 ...


1

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.


1

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. ...


1

While this is borderline a product recommendation question, there is an entire class of hardware encoders that support h.264. The cheapest ones I know of are made by Black Magic Design. Matrox also makes some pretty affordable ones. Be aware you are still talking about a $200 - $500+ device for doing the real time encoding though.


1

It appears you do not have the necessary codec to play the video in mplayer. You will need to find a codec that can decode it. I can't tell from the posted information what codec it is.


1

Most NLE's will allow you to import a still image in the form of how long you want it to appear in the timeline assuming you have set the project properties to some standard frame rate such as 30 fps or 24 fps etc. In Vegas Pro I can set the time a still picture should appear on the timeline, from a fraction of second to several seconds. If I set this to 1 ...



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