Repair broken avi file with known codec and frame size

Question

Is there a way to fix a broken avi (computer powered off during acquisition) if we know the frame size and the encoder? Opening in VLC and repairing it does not work. I have tried following some top answers from (How can I repair a broken AVI file?). I have tried copying with ffmpeg, which gives the following error:

[avi @ 0x16aff60] Format avi detected only with low score of 1, misdetection possible!

mediainfo of Ok file:

Video
ID                                       : 0
Format                                   : JPEG
Codec ID                                 : MJPG
Duration                                 : 1h 29mn
Bit rate                                 : 51.0 Mbps
Width                                    : 4 704 pixels
Height                                   : 3 500 pixels
Display aspect ratio                     : 4:3
Frame rate                               : 3.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:4:4
Bit depth                                : 8 bits
Compression mode                         : Lossy
Bits/(Pixel*Frame)                       : 1.033
Stream size                              : 32.1 GiB (100%)

mediainfo of broken file:

General
File size                                : 32.8 GiB

Answer 1

Since the codec is MJPG, the whole video stream is just a bunch of JPEGs. Any signature-based file recovery software will be able to extract the JPEGs for you - try Photorec or Recuva and make sure to set it to exhaustive/deep scan. If this fails, and you're sure the codec was MJPG, there's most likely no intact data at all in that file.