CHDK RAW Video? - page 2 - RAW Shooting and Processing - CHDK Forum

CHDK RAW Video?

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Re: CHDK RAW Video?
« Reply #10 on: 26 / December / 2013, 16:33:58 »
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Good points.  I realize the h.264 compression would be a separate engine.  As far as an ARM codec, for comparison you can do real-time decoding of MPEG on very low performance systems http://www.rockbox.org/wiki/PluginMpegplayer#Performance

And there's codecs which are very fast encoding on PC.  I'm sure there's a tradeoff somewhere between compression and bandwidth which maximizes resolution, but certainly you're not going to get full resolution.

 Do you know how the HDR sensor mode in magic lantern works?  Does it still send the data directly to the compressor?

I wonder if you could send half an image over USB and write the other half to SD card? Overclock the CPU?

I tried two cameras, and you're right, they only show over HDMI in playback mode.  The quality of the images seems full, but the status overlay is lo-res.  There might be some hack to enable live view.

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Offline reyalp

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Re: CHDK RAW Video?
« Reply #11 on: 26 / December / 2013, 18:29:26 »
Good points.  I realize the h.264 compression would be a separate engine.  As far as an ARM codec, for comparison you can do real-time decoding of MPEG on very low performance systems http://www.rockbox.org/wiki/PluginMpegplayer#Performance
I am not totally unfamiliar with the kind of throughput available on the camera CPU.

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Do you know how the HDR sensor mode in magic lantern works?
I don't but google suggests http://ae.tutsplus.com/tutorials/production/a-simple-way-to-shoot-hdr-video-footage-using-magic-lantern/
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The process is basically shooting two ISO values rapidly, resulting in ghosting artifacts by even minor motion, effectively meaning you should use it mainly on static or slowly moving shots with little-to-no action.

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I tried two cameras, and you're right, they only show over HDMI in playback mode.  The quality of the images seems full, but the status overlay is lo-res.  There might be some hack to enable live view.
The actual live view is not HD resolution, so it would most likely not be a simple unlock. It's possible they removed live view in rec mode because there isn't sufficient bandwidth somewhere to run both. The old cameras with NTSC/PAL out did allow it in shooting mode.
Don't forget what the H stands for.

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Offline srsa_4c

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Re: CHDK RAW Video?
« Reply #12 on: 26 / December / 2013, 18:41:09 »
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Do you know how the HDR sensor mode in magic lantern works?
I don't but google suggests http://ae.tutsplus.com/tutorials/production/a-simple-way-to-shoot-hdr-video-footage-using-magic-lantern/
Quote
The process is basically shooting two ISO values rapidly, resulting in ghosting artifacts by even minor motion, effectively meaning you should use it mainly on static or slowly moving shots with little-to-no action.
He probably means the "new" interlaced-style HDR, which (AFAIK) is done by separately programming the two independent variable gain amplifiers. It also requires raw recording (video or still image), any in-camera processing (de-bayer, etc) destroys more or less image data.

Re: CHDK RAW Video?
« Reply #13 on: 26 / December / 2013, 21:15:14 »
Yes, that's exactly what I mean.  It seems possible to do raw recording.

Also, yes, I've used SD video out as a type of live webcam before (the lens keeps retracting though).  You can do uncompressed video in this way, but it's not very interesting.

I'm basically trying to say, there's hope yet :)


 

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