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6

Yes, it's possible. What you need to do is demux and remux. Check out free tools like VirtualDub and Any Video Converter to split the original into separate streams, add what you want using Audacity or similar, then re-multiplex them together using a tool like AviMux. The video can remain unchanged.


5

What you are missing is that not every frame is stored as a picture. A large number of frames are stored simply by keeping track of what changed from the previous picture. If you think about most video, not a whole lot is actually changing since the majority of the scene stays the same or moves in a similar pattern. By describing only the changes, the ...


4

The short answer is "No." DVD by definition is limited to 720x480 video with a fairly low bitrate, compressed specifically with MPEG-2. There is absolutely no way to make your HD video look just as good with those constraints. Some DVD players do let you play .mp4, .mkv, or whatever files that happen to be stored on a DVD, but that isn't a standard ...


4

The key is to dial in the bitrate - you'll need about 800kbps video with 100kbps audio to hit 200MB. That's low for for SD resolution, but it might be good enough for you. Also look for software that has an option for 2-pass encoding. Try Expression Encoder, Adobe Media Encoder, or Sorenson Squeeze.


3

I assume the actual data rate is 3.3 Mb/s, not MB/s (bits, not bytes). This is very low for 1080p60, and artifacts are likely at such a low rate. You might consider capturing at at least double that rate. Alternatively (or also), halving the frame rate to 29.97 would double the effective bit rate. You would be trading some motion artifacting for less ...


3

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 ...


3

A really good program you can use is Handbrake. It's a very popular program among so called "pirates" because it's really good at getting a high quality even at tiny file sizes. And this is with good reason, because the main purpose of Handbrake is, indeed, to make the movies small with high quality. Personally I use it when I distribute my short movies on ...


3

Unacceptable is in the eye of the watcher, so that part is tough to answer. Distinguishable is easier: yes, there will be a difference. It will not be obvious in every frame or circumstance, but it will be there. If you simply truncate the lowest bit, it will raise the noise floor and the effect will be most evident in low light areas. So, it will look ...


2

Compression codecs and methods are also based extensively in the field of Psychoacoustics. For this, I thoroughly recommend the books available from the Focal Press, such as this one


2

A single layer DVD has about 4.5 GB of capacity, a dual layer DVD has about 8.5 GB of capacity. Some of this space is taken up by menus and special features, but that still leaves plenty of room for video with minimal compression. Take a look at the "blocky" videos - they have probably been re-compressed down to 700MB (so they can fit on a CD-R blank) or ...


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

There is no way around needing more data rate to capture that much video information. It sounds like the camera probably isn't actually capable of delivering 1080P/60 but that they use a very low quality version so they can slap the label on the box. Data rates are generally measured in Mb(bits)/sec rather than MB/s, but even if your suggested rate ...


2

Vantolinomo - You might just be experiencing 'gamma shift' which can happen when you are exporting to H264 video. You can find a tutorial to fix this here: http://www.videocopilot.net/blog/2008/06/fix-quicktime-gamma-shift/


1

Compressor 4.1 does not support distributed renderings for other programs (such as FCPX). This is documented on page 11 of the Transitioning To Compressor document. You can only do distributed encoding for transcodes defined entirely within Compressor, not renders.


1

The best compression would come from a variable frame rate format. Variable Frame Rate formats are designed to adjust their frame rate based on the level of activity in the video. For something with a very low effective framerate, this would allow it to store the image far fewer times and simply describe how long the image should stay up for. It would ...


1

While I am not 100% sure, I believe that the effect you are talking about (such as how it is seen in Command & Conquer) is a result of applying a reduced color pallet to the video. For old games, disk space was at a premium and file sizes had to be kept exceptionally small and modern advanced compression was too processor intensive to be used. ...


1

It sounds to me like you're describing interlaced video. Which is, yes, "some kind of compression trick aimed at CRT displays," but has more to do with the perception of smooth motion, and less to do with brightness. Basically, every other line comes from the next video frame, which may have the effect of making the lines brighter or darker.


1

What is your definition of huge and what is your definition of high quality? Size is directly related to compression and compression is directly inversely related to quality for the most part. Some amount of compression can be had for free using lossless compression or near free with more efficient pattern finding for lossy compression, but for the most ...


1

When video or audio data is compressed, it works by two different mechanisms. The first (which is the only one used by lossless compression) is to look for patterns that are repeated. When patterns are found, it can store the data once and reference the stored copy. The second is only used lossy compression and involves discarding the least significant ...


1

Can you provide more details about the source format, as in resolution, video & audio codec details etc? My stock answer is to use ffmpeg with Avanti for the frontend. A starter tutorial is here


1

It is unlikely to be noticeable. This is basically the principal on which steganography operates. It changes the least significant bits in images and video such that there is not a noticeable change in the final image, however software can later pull out the data without it being obvious that the data was there. Without access to the original image it is ...


1

There are a few mistakes in your math. First, you are multiplying an entire group of pictures (7 frames) by 25, that would be 7 seconds of video, not one. Second, you are not considering that the first I frame of one set is the last of the next, so it should be assumed that the sequence that would be used is IBBPBBIBBPBBIBBPBBIBBPBB... It would make ...


1

I would try uploading the video to vimeo as well. Or, if you have your own website, uplaod it to there and create a simple page with an embedded player. My experience is that YouTube sometimes adds a LOT of artifacts when it recompresses things. I've often experienced the problem you're having when I work with YouTube, but rarely with vimeo. If Vimeo ...


1

If anyone else is interested, Coursera just started a "Fundamentals of Digital Image and Video Processing" in partnership with Northwestern University. From the syllabus, it looks like many relevant topics will be explored. https://www.coursera.org/course/digital The course started on March 31, 2014. Here is the general course outline: Introduction, ...



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