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video with the CHDK memory card seems pixelated

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video with the CHDK memory card seems pixelated
« on: 09 / April / 2012, 06:40:52 »
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While taking a (regular) video shot with the camera when it has the memory card with CHDK, I'm getting very pixelated videos. 

How do I fix this (get my videos to look normal again)?

(I don't know if this is relevant, but the memory card with CHDK is 2 GB, as compared to my usual ultra 4 GB memory card)

Re: video with the CHDK memory card seems pixelated
« Reply #1 on: 09 / April / 2012, 06:51:16 »
Check, whether you have set 'quality override' in 'video options'. You can disable these overrides.
if (2*b || !2*b) {
    cout<<question
}

Compile error: poor Yorick

Re: video with the CHDK memory card seems pixelated
« Reply #2 on: 09 / April / 2012, 07:32:34 »
these are the CHDK video settings -
- Video Mode - Bitrate
- Video Bitrate - 1x
- Video Quality - 84
- Clear videoparams on Start? [ ]
- Fast Video Control? [ ]
- Video Quality Control? [ ]
- Enable Optical Zoom [ ]
- Show remaining videotime? [ both]
- Refreshrate (~sec) [ 1]

Re: video with the CHDK memory card seems pixelated
« Reply #3 on: 09 / April / 2012, 07:40:42 »
It was the "Video Mode" on "Bitrate" instead of "Quality", right?


Re: video with the CHDK memory card seems pixelated
« Reply #4 on: 09 / April / 2012, 17:49:13 »
I meant 'Video quality' rather, but value 84 seems to be ok. However you have unset the 'Video quality control' so the quality should not be overriden by CHDK.

Did you try to use the same SD card without CHDK loaded? Or maybe try to rename the CHDK config file (this one with .CFG extension in CHDK/ directory - this will clear all CHDK settings).
if (2*b || !2*b) {
    cout<<question
}

Compile error: poor Yorick

Re: video with the CHDK memory card seems pixelated
« Reply #5 on: 09 / September / 2012, 06:29:30 »
Hi all,

Am desperate for some help - arguably more so than others..!

A while ago i decided to have a play and added chdk to my canon ixus 85. all seemed fine. however, i didn't check the video function on it.

In short, i recorded vid clips of my first child being born, only to find them to playback very pixelated! The first second is fine, but then it changes to be pixelated. See attached.

Can anyone let me know how i can repair these please..??  :( :( :( :(

The media info as seen in media player:

General
Format                         : AVI
Format/Info                    : Audio Video Interleave
File size                      : 4.58 MiB
Duration                       : 12s 867ms
Overall bit rate               : 2 989 Kbps
Mastered date                  : Fri Aug 31 21:00:02 2012
Writing application            : CanonMVI06

Video
ID                             : 0
Format                         : JPEG
Codec ID                       : MJPG
Duration                       : 12s 867ms
Bit rate                       : 2 278 Kbps
Width                          : 640 pixels
Height                         : 480 pixels
Display aspect ratio           : 4:3
Frame rate                     : 30.000 fps
Color space                    : YUV
Chroma subsampling             : 4:2:2
Bit depth                      : 8 bits
Scan type                      : Progressive
Compression mode               : Lossy
Bits/(Pixel*Frame)             : 0.247
Stream size                    : 3.49 MiB (76%)

Audio
ID                             : 1
Format                         : PCM
Format settings, Endianness    : Little
Format settings, Sign          : Signed
Codec ID                       : 1
Duration                       : 12s 867ms
Bit rate mode                  : Constant
Bit rate                       : 705.6 Kbps
Channel(s)                     : 1 channel
Sampling rate                  : 44.1 KHz
Bit depth                      : 16 bits
Stream size                    : 1.08 MiB (24%)
Interleave, duration           : 990 ms (29.69 video frames)
Interleave, preload duration   : 1000 ms




*

Offline reyalp

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Re: video with the CHDK memory card seems pixelated
« Reply #6 on: 09 / September / 2012, 15:34:11 »
Can anyone let me know how i can repair these please..??  :( :( :( :(
If the video was recorded at low quality, the information is gone, it cannot be repaired. Based on the stream size and bit rate, this seems to be the case. Sorry :(
Don't forget what the H stands for.

Re: video with the CHDK memory card seems pixelated
« Reply #7 on: 09 / September / 2012, 16:03:33 »
Second time in about 3 months somebody has hit this : http://chdk.setepontos.com/index.php?topic=8183.msg86032#msg86032

Are the default settings "wrong" - should things like "Video Quality Control" be defaulted "Off" ?  If you load CHDK and the it affects video quality (even though you have never visited the Video Menu) that could be annoying.
Ported :   A1200    SD940   G10    Powershot N    G16


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Offline reyalp

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Re: video with the CHDK memory card seems pixelated
« Reply #8 on: 09 / September / 2012, 17:08:32 »
Are the default settings "wrong" - should things like "Video Quality Control" be defaulted "Off" ?  If you load CHDK and the it affects video quality (even though you have never visited the Video Menu) that could be annoying.
Yes, if it affects video quality by default, that's quite wrong.

This is actually a bit complicated because mjpeg and x264 cams behave differently.

On my a540, with default settings
- video mode is 'bitrate', Only 'bitrate' and 'quality' are available, there is no "off" option.
- bitrate is 1. This should be default quality, incorrect implementation could get the default wrong.
- quality is 84, which should not affect anything if bitrate mode is selected. There should really be an "off" option, but this probably requires changing movie_rec.c for all affected cameras.
-'fast video control' is unchecked. This gives you (dangerous) shortcuts to pause/resume recording.
-'video quality control' is checked, but in the code this is actually conf.fast_movie_quality_control, which enables keyboard shortcuts (see the lovely mess that is kbd_use_up_down_left_right_as_fast_switch). Even if the defaults are correct, you could accidentally have changed it while recording.

Conclusion for mjpeg cameras: 'video quality control' should default to off. Ideally, it should be possible disable the video override code completely.

x264 to follow...

d10:
- 'video mode' = "default", other option is "quality"
- 'quality' = 84
- 'video quality control' = checked
in movie_rec.c, there should be no effect when video mode is 'default' so this is safe, although 'quality control' should probably be unchecked by default anyway.

« Last Edit: 09 / September / 2012, 17:26:34 by reyalp »
Don't forget what the H stands for.

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Offline srsa_4c

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Re: video with the CHDK memory card seems pixelated
« Reply #9 on: 09 / September / 2012, 17:55:06 »
Though not bitrate related, I have a small collection of cameras which can give a nasty surprise when trying to record a movie:
http://chdk.wikia.com/wiki/User:Srsa_4c/Forgotten_stuff , section "Cameras that may crash while recording a movie". Not likely this could change unless people with those cams come here willing to test...

 

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