conv: Support buffer strides on unpacked raw buffers #6
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pixutils/conv/raw.py
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| data = data.reshape((height, len(data) // height)) | ||
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| # Remove padding if present | ||
| padded_width = width * bits_per_pixel // 8 |
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How did you test this?
The unpacked data is in 16-bit containers for 10/12/16. The above calculates a packed width.
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Aha, so most of my current test on this only displays the top left corner of a 20Megapixel image - so I could easily have got this wrong in fact.
This patch does however now let me /see/ the top left corner which is what I needed ;-) but yes - it probably needs retesting without my artificial crops added to verify the whole image.
I'm testing on a Raspberry Pi 5 capturing SRGGB16.
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Ok - so perhaps this only worked for me because I was fortunately using SRGGB16 to match the 16 bit alignement of the data coming in by chance.
So perhaps regardless of bits_per_pixel, we should always do padded_width = width * 2; /* 16 bit data */
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Nope - now I see it. Particularly retesting on a system with 12 bit data instead of 16 bit data ;-)
# Remove padding if present
- padded_width = width * bits_per_pixel // 8
+ # The unpacked data is stored in 8 bits for 8bpp, and 16 bits for 10/12/16bpp.
+ bytes_per_pixel = 1 if bits_per_pixel == 8 else 2
+ padded_width = width * bytes_per_pixel
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or more generically to support future higher bit depths:
# The unpacked data is stored in 8 bits for 8bpp, and 16 bits for 10/12/16bpp
bytes_per_pixel = (bits_per_pixel + 7) // 8
padded_width = width * bytes_per_pixel
Platforms may configure buffers that have a larger buffer stride than the image width to support hardware padding restrictions. The raw_to_bgr888() function already accounts for this when operating on prepare_packed_raw(), however prepare_unpacked_raw() raw is missing the handling for buffer strides. Reshape the data, and delete the padding accordingly. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
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@tomba Any happier with this now ? |
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Platforms may configure buffers that have a larger buffer stride than the image width to support hardware padding restrictions.
The raw_to_bgr888() function already accounts for this when operating on prepare_packed_raw(), however prepare_unpacked_raw() raw is missing the handling for buffer strides.
Reshape the data, and delete the padding accordingly.