Higher framerate capture might be posible via hdmi or usb output? - Feature Requests - CHDK Forum supplierdeeply

Higher framerate capture might be posible via hdmi or usb output?

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Offline Ironwave

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Idea-
- streaming data directly via hdmi or usb to pc and display there, or save there, skipping on board memory or sd card completely.

researched= hdmi speeds is 742.5 Mbps on old cables, even faster on new ones.
                  = class 10 sd cards is fast, but still much slower then hdmi, less then 312 Mb/s.

=Theory,   thus one can at the very least double your cams fps capability especially those ones that's in the access of 1 fps.

Am I completely nuts or might this be do-able?
Sx40hs-learning how not to just point and shoot.
Next stop; Astrography.

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Offline lapser

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #1 on: 01 / January / 2013, 17:03:56 »
Continuous mode can already save 4000x3000 pictures at 2 FPS to an SD card, and at over 3 FPS on some cameras. Even if you could transfer them off the camera instantly, I don't think the camera could take pictures much faster than that.

As of now, there's no way to abort the file save process after raw_save_file(). That would be a worthwhile hack to do, for 2 reasons.

1. You wouldn't have to save jpgs all the time when saving raw files with CHDK.

2. I've developed functions that measure exposure from the raw buffer that can be used instead of the camera meter for high speed shots. But you can only change the exposure on the next shot, since you're measuring after the fact. If you could discard the shot after measuring, you could take a second shot with the proper exposure within about 0.3 seconds, which is actually faster than the camera pre-shot meter.

I like your idea, but I think it can be achieved in software.
EOS-M3_120f / SX50_100b / SX260_101a / G1X_100g / D20_100b
https://www.youtube.com/user/DrLapser/videos

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Offline reyalp

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #2 on: 01 / January / 2013, 17:11:45 »
What "data" do you have in mind? The live view is relatively low res (and can already be streamed over USB using the PTP extension). I expect the live view scaled up for HDMI (although it would be interesting if someone with an HDMI capable cam can verify), so isn't likely to improve things.

HDMI video playback and image review is presumably higher res (and verification would be interesting).

When recording HD video, there might be some data that could be streamed, but replacing the live view on HDMI seems like a tall order. Streaming over USB (after compression) might theoretically be possible, but likely tricky.

If you are thinking about stills shooting, we are currently working on sending that directly over USB. However, it won't speed up shooting significantly, if at all. Sending it over HDMI seems unlikely.
Don't forget what the H stands for.

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Offline srsa_4c

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #3 on: 01 / January / 2013, 17:19:52 »
AFAIK HDMI is inactive in rec mode on all PowerShots I checked (in the manual)...


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Offline reyalp

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #4 on: 01 / January / 2013, 17:24:04 »
AFAIK HDMI is inactive in rec mode on all PowerShots I checked (in the manual)...
Ah, I just assumed it worked like tv-out. Thanks for the correction.

edit:
In that case, I guess in theory it might be possible to turn on the HDMI engine and send arbitrary stuff to it, but OTOH, the reason it is turned off might be system load.
Don't forget what the H stands for.

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Offline lapser

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #5 on: 01 / January / 2013, 17:26:47 »
If you are thinking about stills shooting, we are currently working on sending that directly over USB. However, it won't speed up shooting significantly, if at all. Sending it over HDMI seems unlikely.
I've been trying to get someone interested in the new Flashair wireless card from Toshiba.
http://www.toshiba-components.com/FlashAir/index.html

It sounds a lot better than EyeFI cards, but I don't know anyone who has tried it. It looks like you could program CHDK to send and receive any type of file, both ways, so you could upload CHDK updates and scripts as well as download pictures. I'll probably have to get one myself and see if I can interface it to Lua scripts or something. But this would be right up your alley, reyalp. Are you interested?
EOS-M3_120f / SX50_100b / SX260_101a / G1X_100g / D20_100b
https://www.youtube.com/user/DrLapser/videos

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Offline Ironwave

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #6 on: 01 / January / 2013, 17:28:36 »
I was thinking of still shooting, then maybe streaming that over hdmi (even if bit lower ress) since it seems faster.
Pity if that seams unlikely.
Maybe I should check out what my camera's capability is on Continuous mode under chdk.
I didn't think there would be a speed increase.

I was put off a bit by chdk since there was some issue to focus to infinity with chdk on my camera, but it seems to be right now, after some tweaks.

Thanks for the quick answers :-D
Sx40hs-learning how not to just point and shoot.
Next stop; Astrography.

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Offline Ironwave

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Sx40hs-learning how not to just point and shoot.
Next stop; Astrography.


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Offline Ironwave

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #8 on: 01 / January / 2013, 17:48:00 »
Oops, I see you mention you DIdn't like these.
Sx40hs-learning how not to just point and shoot.
Next stop; Astrography.

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Offline lapser

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Re: Higher framerate capture might be posible via hdmi or usb output?
« Reply #9 on: 02 / January / 2013, 05:28:24 »
Oops, I see you mention you DIdn't like these.
I haven't tried the EyeFI, but I don't think they allow uploads to the camera, or downloading all file types. The Flashair uses a new standard that allows peer to peer, and has an interface that the camera can use if it's aware of it. That may provide new opportunities. There's a new android app that sounds interesting, too.

http://www.amazon.com/Toshiba-Notebooks-FlashAir-Wireless-PFW008U-1ABW/dp/B00AARIEVK/

They've come down in price from $100 to $54.86 in the US now (for 8GB). So I just talked myself into ordering one. If I can't figure out how to get it working with CHDK, maybe I'll mail it to reyalp. I bet he could make it purrrrr.

Do you know how wifi speeds compare to USB in cameras?
EOS-M3_120f / SX50_100b / SX260_101a / G1X_100g / D20_100b
https://www.youtube.com/user/DrLapser/videos

 

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