AVC Intra is a professional H264-compliant recording format developed by Panasonic.
It comes in two flavors: 1920x1080 and 1280x720, and two bitrates: 50 Mbit/s and 100 Mbit/s
AVC Intra codec for Mac is available free of charge in Panasonic website.
The specificity of AVC Intra is to use intra-frame compression only. Unlike other H264 formats, it does not use inter-frame compression (also called temporal compression). This brings obvious advantages for editing, since random access to each frame is very fast, and avoids problems derived from long GOPs (groups of pictures) like pixellation and propagation of defects over many frames.
Treasured is capable of detecting and previewing AVC Intra media in damaged files or disks.
AVC Intra media is repaired without major problem, even in corrupt MXF files.
A sample of a good file is recommended.
How to repair a corrupt AVC Intra clip?
The easiest way is certainly to ask our Movie Repair Service to do it for you.
But for those who can program, here you have a few tips:
Each frame is an I-frame and contains all the information necessary to decode. The median size of a frame is 200000 bytes (200kb). Frames start with this pattern:
00 00 00 01 65 88 81 xx xx AE 20 xx xx xx 00 (720p variant)
00 00 00 01 65 88 81 xx 04 2B (1080p variant)where xx represents a byte that can take any possible value.
Note that this corresponds to a raw H264 bitstream (00 00 00 01 header) instead of a group of QuickTime H264 samples as in most H264 applications (where the first four bytes encode the sample size)
There is a different way to look at AVC Intra raw data: AVC Intra uses with fixed-length samples (that contain some header information and H264-compliant bitstream with 0x00 padding)
- 236032 bytes for 1280x720
- 472064 bytes for 1920x1080
Once frames are parsed, the common repair techniques can be used: