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Questions tagged [codec]

Shorthand for "Encoder/Decoder". A codec allows to convert data into a different representation and decode it again. Codecs are mostly used in signal transmission, e.g. for audio/video playback or streaming.

Codec is shorthand for "Encoder/Decoder". A codec allows to convert data into a different representation and decode it again. Codecs are mostly used in signal transmission, e.g. for audio/video playback or streaming.

Note that "codec" is typically just the name for a standard that describes how to engineer "encoders" and "decoders". For example, MP3 is a codec, and LAME is an encoder for it.

In practice, this distinction isn't made, and therefore "codec" will mostly be used synonymously with "encoder". For a list of popular codecs and the difference to actual file formats, see: What is a Codec (e.g. DivX?), and how does it differ from a File Format (e.g. MPG)?

Some popular codecs on Super User include:

  • (MPEG 2, Layer III)
  • (Advanced Audio Coding)
  • (H.264, MPEG-4 AVC, MPEG-4 Part 10)
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What is a Codec (e.g. DivX?), and how does it differ from a File Format (e.g. MPG)?

I'm so confused... what is the difference between an audio/video codec (which apparently is a shorthand for "encoder/decoder", kind of like how "modem" is really "modulator/demodulator") and an audio/video format? (Am I even using the correct…
user541686
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Use ffmpeg copy codec to combine *.ts files into a single mp4

I've got a bunch of ts segments described by a single index.m3u8 file: index.m3u8 segment1_0_av.ts segment2_0_av.ts segment3_0_av.ts segment4_0_av.ts segment5_0_av.ts I know they are all encoded the same way. ffprobe gives me the…
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What's the difference between FFmpeg's "-vcodec copy" and "-sameq"?

What is the difference between using -vcodec copy and -sameq with FFmpeg? Do they do the same thing?
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How do I find the codec for an AVI?

How can I find which codec an AVI file needs? A method that does not require downloading a program would be preferred (such as looking at the file in notepad).
C. Ross
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MP3 vs M4A (AAC): what is the audio codec for portable devices which gives maximum independence?

A couple of years back MP3 was the most supported format for portable devices. Then Apple came along and wiped the floor of all the portable devices with the iPod as well as the iPhone. They clearly favour M4A (AAC). When to choose, right now, the…
akira
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How does bitrate differ for the same resolution and framerate?

Reading about video quality I found that it depends of resolution, frames per second and bitrate, which decides the size of the video. My question is how the bitrate is calculated and how it can differ. Let's say a video has a 360x240 resolution. It…
vincent mathew
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Which codecs are most suitable for playback with Windows Media Player on Windows XP?

I need to encode a short video in a format that can be played with windows media player on windows xp without installing any additional codecs. For the recoding process I'm using ffmpeg. I've already tried the msmpeg4v2 codec but the quality is…
ThiefMaster
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Why is encoding VP8/9 so slow compared to H.264?

Recently I wanted to try out the Webm codecs VP8 and VP9 but when I ran ffmpeg to encode a H.264 MP4 file into one of the other two codecs, I realized that the encoding is (by almost an order of magnitude) slower. A 1080p30 video from H.264 to VP9…
comfreak
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How to fix choppy sound replay with VLC

I've got a problem with vlc playing some file formats, for example mkv or m2ts (I didn't notice this problem with avi though). The sound plays ok, than dissappears for a second or two, than re-appears. It occurs around once every 10 seconds. This is…
Arsen Zahray
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How can I get thumbnails in Windows Explorer for .3gp and .webm files?

Basic set up On my Windows 7 Professional 64-bit system I have installed K-Lite Codec Pack 7.10 and K-Lite Codec Pack 64-bit 4.6 with only the following options (the idea being to only add what's missing and not replace what's already there from…
Michiel van Oosterhout
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How can I make Windows 7 show thumbnails for MKV files?

I'm using Windows 7 64-bit and have installed the latest Haali Media Splitter. How can I make Windows Explorer show thumbnails for MKV files?
Henry
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Install codecs for VirtualDub

I have many video codecs installed on my machine but Virtualdub only lets me choose from a very basic selection. Do I have to manually point VirtualDub to the codecs somehow?
maloo
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ffmpeg: Could not find codec parameters for stream 0 (Video: h264) unspecified size

I try to convert a video from .raw to .mp4. For this reason I did download, build and install both x264 and ffmpeg. However, command: ffmpeg -f h264 -i output.raw -vcodec copy output.mp4 fails with error (shown in picture below). Is there any way to…
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Recommended settings to convert Opus to AAC

I am downloading some music from Youtube, and it seems that in most cases (popular videos), the best quality audio is an opus file. I know that (1) Opus is the newest and more efficient codec, and (2) converting from one lossy codec to another is…
Peter K.
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Using a lossless video codec for archiving (monochrome) scientific video data

Basic question: what is a suitable codec for storing/archiving scientific video data in a lossless manner? I am trying to help my research group out with storing/archiving some videos recorded with a microscope. These (grayscale) videos are in…
Nick C.
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