Author Topic: Strange variable gain MLVs come out from mlv_lite/crop_rec tandem.  (Read 1032 times)

bouncyball

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Hey guys I have strange behavior (channel gain or channel black/white level changes in time, within some range and then stops) when recording in 3K crop_rec mode (5D3 firmware 1.1.3). Here is the sample MLV link.

Reproduce like this:

Use crop rec with raw recording (I used 2880 width with 2.35 aspect for continuous recording). Record small clip, check, all must be fine. Then use 10x magnification to focus on something. Switch back to 1x mode (ML slow preview) and record again about a 30 seconds.

@a1ex: I guess this footage can not be recovered fully right?

bouncyball

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Re: Strange variable gain MLVs come out from mlv_lite/crop_rec tandem.
« Reply #1 on: October 27, 2018, 12:03:32 PM »
The histogram changes dramatically on blacks and shadows side.

a1ex

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Re: Strange variable gain MLVs come out from mlv_lite/crop_rec tandem.
« Reply #2 on: October 27, 2018, 12:27:28 PM »
Very interesting; in particular, the defect appears progressively *after* recording starts...

Clean video mode switching is pretty difficult to figure out...

bouncyball

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Re: Strange variable gain MLVs come out from mlv_lite/crop_rec tandem.
« Reply #3 on: October 27, 2018, 03:21:33 PM »
I guess not quite from the start. I cut 200 frames from the beginning with mlv_dump.

Or maybe this effect is not noticeable from the beginning and after about 230 frames it is starting to be noticeable, then changes quite rapidly until it is unnoticeable again after about 350 frames.

Danne

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bouncyball

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Re: Strange variable gain MLVs come out from mlv_lite/crop_rec tandem.
« Reply #5 on: November 07, 2018, 08:12:49 AM »
Some news about topic. Raw buffer height is different. I guess it is a result of going into 10x zoom and returning to normal (buffer changed but has not reset)

Note: I have not touched any registers or anything else. The build versions are in the MLV VERS header

Corrupted VariGain MLV: Link
Code: [Select]
Block: RAWI
  Offset: 0x00000034
  Number: 1
    Size: 180
    Time: 1.549000 ms
    Res:  2880x1226
    raw_info:
      api_version      0x00000001
      height           1350
      width            3224
      pitch            5642
      frame_size       0x007438BC
      bits_per_pixel   14
      black_level      2047
      white_level      16200
      active_area.y1   30
      active_area.x1   146
      active_area.y2   1350
      active_area.x2   3224
      exposure_bias    0, 0
      cfa_pattern      0x02010100
      calibration_ill  1

Normal MLV: Link
Code: [Select]
Block: RAWI
  Offset: 0x00000034
  Number: 1
    Size: 180
    Time: 0.744000 ms
    Res:  2880x1226
    raw_info:
      api_version      0x00000001
      height           1950
      width            3224
      pitch            5642
      frame_size       0x00A7E02C
      bits_per_pixel   14
      black_level      2047
      white_level      16200
      active_area.y1   30
      active_area.x1   146
      active_area.y2   1950
      active_area.x2   3224
      exposure_bias    0, 0
      cfa_pattern      0x02010100
      calibration_ill  1