Can't skip the data loss frame in the IsochronousStream class

Peter-St / Android-UVC-Camera

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Can't skip the data loss frame in the IsochronousStream class #10

Closed Jade-source closed 3 years ago

Jade-source commented 4 years ago

Hi, Peter-St

I found that in the Galaxy(android 9 series) accepts packets with data loss without skipping them.

As far as I've checked, IsochronousStream Class can't skip the problematic frame. The reason seems to be the lack of defensive code to detect frames.

In IsochronousStream class, the current header length, flag, and data length are only detected, So frame detection is improved by adding FID and EOF, but skip is not perfect.

26 03 2020_18 05 17

Peter-St commented 4 years ago

You are right.

I experimented some time ago on this behavior, but wasn't able to solve it. Any help would be welcome to solve this issue.

Ehm, this issue could be solved, by an analysation of the bytes of each frame.
A normal frame's bytes looks different to each other (the bytes were displayed for example in the testrun button under "set up the device" menu. I'll think a problematic frame lists a lot of bytes in the same value (hex from 0 x00 to 0xff).

Peter-St commented 3 years ago

The latest Approach over the LibUsb Driver should solve this issue. Update the app to the latest version and set up the Camera with the LibUsb driver.