H.264 at 2.5k?

Started by Malio94, October 21, 2013, 02:17:01 AM

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Malio94

Hi all,

I've been thinking of some ways other than RAW to get more out of a canon dslr. And I started wondering if it would be possible to unlock the ability to record H.264 video at higher resolutions than 1920x1080. (on the 600d and other eos cameras)

While the 600d shoots video at 1920x1080, it's actual sensor is capable of capturing images at 5184 x 3456. This means that when recording video only around 1/5th of the sensor is being used.

But out of the box, the 600d is capable of recording 1920x1080 video at a maximum of 30fps.

This means that for each second of video the 600d is capable of processing 62,208,000 pixels.
(1920x1080=2,073,600    x30= 62,208,000)

Lets imagine for a second that it IS possible to record higher than 1080p video with the 600d.

If you were recording at say 2112x1188 (a resolution 1.1x larger than 1080p) at 24 fps, the 600d would be processing 60,217,344 pixels per second.
(2112x1188=2,509,056      x24=60,217,344)

This means that at the higher resolution, the camera isn't being pushed any harder than it would be from normal use.

So what do you guys think? Is it theoretically possible to enable the camera to do something like this?

N/A

I don't think they can completely access the parameters of the h264 encoder, but the best bet would probably be to use it's 3x crop mode to capture > 1080p. I've asked before though and it doesn't look very likely.
7D. 600D. Rokinon 35 cine. Sigma 30 1.4
Audio and video recording/production, Random Photography
Want to help with the latest development but don't know how to compile?

Malio94

Hmm didn't know what that crop mode did till today lol. Makes getting macro shots super easy.

N/A

Also eliminates aliasing and moire, but you'll get slightly more noise in your shots.
7D. 600D. Rokinon 35 cine. Sigma 30 1.4
Audio and video recording/production, Random Photography
Want to help with the latest development but don't know how to compile?

Malio94

Also, Certain cameras with fast cards can go beyond 1080p in RAW so why couldn't it be done with H.264? (or some other compressed codec.)

bnvm

It is hard to understand because you don't yet know the difference between raw video and h264. They are very separate things and just because you can do something with one doesn't mean you can do it with the other. Everything you are asking has been asked and answered many times before.


bart

Quote from: Malio94 on October 21, 2013, 04:11:20 AM
Hmm didn't know what that crop mode did till today lol. Makes getting macro shots super easy.

It also gives you a whole lot larger depth of field (DOF) at the same field of view (magnification of the subject). Distance to the subject matters for DOF. And you sort of override the closes focus distance by magnifying the image. A 50mm with closest focus at 0.35m can be used for macro work. You suddenly have a 150mm at 0.35m. Try to find a non-macrolens at 150mm that can focus this close. And finally you can choose to make the working distance bigger which is nice for alive insects.

mrnv45

After seeing 3.5k is it coming to the 7d.

1%

The HW encoder can't do more than 1920x1080.. thats why it scales LV size to that. Also all encoding is fixed... ie there is 720, 1080P and 640x480. Its in the datasheet for similar chips.  Also why 1dC is mjepg for the 4K... so really the breakthrough would be with using the jpeg encoder real time and at whatever size we want.

N/A

Anyone try uprezzing h264 in post to something like 2560x1440? Maybe not the normal line-skipped video, but 3x zoom footage may possibly uprez decently. Going to test this tomorrow.

Another idea would be to encode crop marks (2.39:1 for example) straight into the video feed so that the existing video's bitrate (1920x803) could be increased even more. Not a coder though so I have no clue if this is possible.
7D. 600D. Rokinon 35 cine. Sigma 30 1.4
Audio and video recording/production, Random Photography
Want to help with the latest development but don't know how to compile?

3pointedit

1% is there any indication for bottlenecks with the jpeg encoder?

I realize that no one knows how to handle that path, but logically I guess it is demosaicing, then resizing, then compressing to save? And is all that triggered by shutter or can it be actuated shutterless like in movie mode?
550D on ML-roids

Malio94

Quote from: bart on October 21, 2013, 08:50:00 AM
It also gives you a whole lot larger depth of field (DOF) at the same field of view (magnification of the subject). Distance to the subject matters for DOF. And you sort of override the closes focus distance by magnifying the image. A 50mm with closest focus at 0.35m can be used for macro work. You suddenly have a 150mm at 0.35m. Try to find a non-macrolens at 150mm that can focus this close. And finally you can choose to make the working distance bigger which is nice for alive insects.

Yeah it's a super useful feature for sure. Like you said in many cases its easier to use the cropped mode then having to deal with extension tubes and the tiny DOF that comes along with them.

myke2242

i like the idea of M-Jepg. i imagine if the hardware encoder is hacked you be more limited in what you could do.

Brawl

Quote from: mrnv45 on October 22, 2013, 01:09:36 AM
After seeing 3.5k is it coming to the 7d.
I do not understand, is 3.5k coming for the 7d? really? raw?


crazyrunner33

The 7D cannot output 3.5K RAW video, it is limited to 2520x1200. While the maximum resolution is 2520x1200, the camera cannot write to the card fast enough to support this resolution for much longer than a few seconds at 24p.
5D Mark III, 7D