AVC VIDEO CODEC CODE
AVC VIDEO CODEC FULL
X264 Full package come with an installer and contains both VFW and CLI with MeGUI.
AVC VIDEO CODEC MP4
If MP4 is chosen, then the audio codec should be Advanced Audio Coding ( -c:a aac).Ī Bash script allowing to perform this transcoding is included in our collection Bash Script for Audiovisual Preservation.To decode use a recent build of FFDShow or a player that supports H.264 internally like MPlayer (there are few interesting frontends for Windows: MPlayerUI, MPlayer Frontend) and VLC (VideoLAN Client). mp4) is choses for wrapping H.264, but others are possible. For silent videos you can replace -c:a copy by -an, for video with sound you may choose another audio codec. The audio codec is specified by -codec:audio, which is usually abbreviated as -c:a ( -codec:a or -c:audio are also possible). You may add the parameter -movflags +faststart allowing to start playing before the whole file is loaded. And, as sadly usual in the computer world, “YUV” stands for the colour space Y′C BC R and not for Y′UV, which is used for PAL video. Therefore, in order to allow possibly all players to read the file, we suggest use to the yuv420p pixel format for dissemination purposes. Many of the non-FFmpeg-based players cannot decode H.264 files having a different chroma subsampling than 4:2:0. This can result in the “YUV” colour space with 4:4:4 or 4:2:2 or 4:2:0 chroma subsampling. The library libx264 supports both, but you cannot combine 8-bit and 10-bit in the same command, you need two commands.īy default the library libx264 will use the chroma subsampling scheme that matches closest the input file’s chroma subsampling. Yuv420p is a common 8-bit and yuv420p10le a 10-bit pixel format. Most of the non-FFmpeg-based players cannot decode H.264 files holding lossless content. The range of the scale for crf and qp for 8-bit is from 0 to 51, where 0 is lossless, approximately 18 is “visually lossless”, 23 is the default value and 51 is worst possible. You can use the parameter -qp 18 (quantisation parameter) rather than -crf 18 (constant rate factor) which gives a similar “visually lossless” result. Slower encoding means that more time is needed, but the compression rate is better. Possible -preset values for the H.264 codec include veryslow, slow, medium, fast and veryfast. If the source should be RGB, then you might choose the video codec libx264rgb rather than libx264. The video codec is specified by -codec:video, which may be abbreviated as -c:v (or -codec:v or -c:video).
![avc video codec avc video codec](https://d3dh6of9cnaq4t.cloudfront.net/Pictures/1024x536/6/5/1/11651_lcevccodeccompressionlcevccom_14142.png)
c:a copy re-encodes the audio stream using the same audio codec output_file path, name and extension of the output file Discussion pix_fmt yuv420p The pixel format for “YUV” colour space with 4:2:0 chroma subsampling and planar colour alignment is chosen for best compatibility. crf constant_rate_factor A parameter of 18 means a “visually lossless” compression. preset preset_value A slower encoding preset means a better compression rate.
![avc video codec avc video codec](https://dl.acm.org/cms/attachment/596bf8a9-13c1-4821-8db7-d9cfb15520d4/dasip21-29-fig1.jpg)
c:a copy \ output_file Command syntax ffmpeg starts the command -i input_file path, name and extension of the input file -c:v libx264 The library libx264 re-encodes the video stream using the H.264 video codec.
![avc video codec avc video codec](https://synopi.com/resources/images/2/encoding-1024x352.png)
c:a copy \ output_file Generic command ffmpeg \
![avc video codec avc video codec](https://i.ebayimg.com/images/g/2nYAAOSw1SxhQ7Wb/s-l1600.png)
Transcode a video file by using the H.264 codec for dissemination purposes.