Difference between revisions of "Working with raw image data"

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(Python)
(Python)
Line 37: Line 37:
 
==Processing==
 
==Processing==
 
===Python===
 
===Python===
* Camera settings: 2592x1936 JPEG, actual pixels available: 2608x1940
+
* Camera settings: 2592x1936 JPEG, actual pixels available - 2608x1940:
  <font size='2em'>#!/usr/bin/python3
+
  <font size='2em'>''#!/usr/bin/python3''
 
  from PIL import Image
 
  from PIL import Image
 
  rawData = open("test.raw", 'rb').read()
 
  rawData = open("test.raw", 'rb').read()

Revision as of 12:22, 12 January 2018

Downloading

  • Available options (channels can be 0..3):
# set receiving buffer size in 4kB pages (thus 4096 equals to 16MB)
echo {size} > /sys/devices/soc0/elphel393-mem\@0/buffer_pages_raw_chn2
# start from the N-th frame position in buffer. Currently, 0 or 1
echo 1 > /sys/devices/soc0/elphel393-videomem\@0/video_frame_number
# initiate transfer, wait for X-th frame (X - absolute frame number), 0 = no waiting
echo X > /sys/devices/soc0/elphel393-videomem\@0/membridge_start2
# copy to file
cat /dev/image_raw2 > /tmp/test.raw
# see in hex
hexdump /tmp/test.raw
# copy to PC
scp /tmp/test.raw user@address:/path/
  • Minimal:
echo 4096 > /sys/devices/soc0/elphel393-mem\@0/buffer_pages_raw_chn2
echo 0 > /sys/devices/soc0/elphel393-videomem\@0/membridge_start2
cat /dev/image_raw2 > /tmp/test.raw

Displaying

ImageMagick

  • Camera settings: 2592x1936 JPEG, actual pixels available: 2608x1940
convert -size 2608x1940 -depth 8 -endian MSB -normalize gray:test.raw -compress lzw result.tiff
  • Camera settings: 2592x1936 JP4, actual pixels available: 2592x1936
convert -size 2592x1936 -depth 8 -endian MSB -normalize gray:test.raw -compress lzw result.tiff

The result is a grayscale tiff

bayer2rgb program

  • Available here.
  • Camera settings: 2592x1936 JPEG, actual pixels available: 2608x1940
bayer2rgb -w 2608 -v 1940 -b 8 -f GRBG -m AHD -t -i test.raw -o test.tiff

The result is a colored tiff image. Pixel values are linear.

Processing

Python

  • Camera settings: 2592x1936 JPEG, actual pixels available - 2608x1940:
#!/usr/bin/python3
from PIL import Image
rawData = open("test.raw", 'rb').read()
imgSize = (2608,1940)# the image size
img = Image.frombytes('L', imgSize, rawData)
img.save("result.jpeg")# can give any format you like .png