Author Topic: Which module can record raw video with lossless compression and lens info?  (Read 430 times)

1400700226

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Hi everyone, my cam is 5dmk3 v1.2.3 with a ef zoom lens.
The lens has some distortion which changes during zooming. So I want to correct it in post with lens profiles, and this requires focal length info in each frame.
The mlv_rec.mo with format v2.0 stores realtime lens forcal length info, which fits my need perfectly. However it can't do lossless compression, so I have no way to record 1080p 30fps 14bit video with it. The mlv_lite.mo in crop_rec experimental build can do lossless compression, but it doesn't save realtime lens info. I tried Danne's build but no difference.
So I want to know am I missed a module with both lossless compression and lens info somewhere?

Thanks in advance!

theBilalFakhouri

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As far as I know mlv_lite has basic metadata which explains why there is no real-time focal length info . . I think it could be implemented into mlv_lite (updating focal length info per frame), personally I don't have an experience with metadata so can't help much here . .

BTW you can use uncompressed 10/12 bit-depth using mlv_rec which requires lower write speed than uncompressed 14-bit, you can find a build here:
https://builds.magiclantern.fm/experiments.html

Under:
"10/12-bit RAW video" or "4K raw video recording; lossless compression"
700D 1.1.5 | no more ISOless LV err 8 / SDR104 @ 240 MHz - Constant! | Fixed Scrambled LiveView in Higher resolution | Real-Time correct framing in the Way

1400700226

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Thanks for your reply.
The problem of 10/12 bit in magic lantern is, it throws the darkest bits away from 14bit, other than the sensor working in 10/12 bit. So there is significant clipping issue while the sensor has DR less than 12 EV.