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[media] doc-rst: add sh_mobile_ceu_camera crop documentation 

Convert it to ReST and add it to media/v4l-drivers book.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Mauro Carvalho Chehab 2016-07-17 19:43:22 -03:00
parent ae9d2873a8
commit 9cbfcd7cf2
2 changed files with 30 additions and 28 deletions
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1
Documentation/media/v4l-drivers/index.rst
View File

@ -34,4 +34,5 @@ License".
pxa_camera pxa_camera
radiotrack radiotrack
saa7134 saa7134
sh_mobile_ceu_camera
zr364xx zr364xx

57
Documentation/media/v4l-drivers/sh_mobile_ceu_camera.rst
View File

@ -1,5 +1,7 @@
Cropping and Scaling algorithm, used in the sh_mobile_ceu_camera driver Cropping and Scaling algorithm, used in the sh_mobile_ceu_camera driver
======================================================================= =======================================================================
Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Terminology Terminology
----------- -----------
@ -12,29 +14,31 @@ combined scales: sensor_scale * host_scale
Generic scaling / cropping scheme Generic scaling / cropping scheme
--------------------------------- ---------------------------------
-1-- .. code-block:: none
|
-2-- -\ -1--
| --\ |
| --\ -2-- -\
+-5-- . -- -3-- -\ | --\
| `... -\ | --\
| `... -4-- . - -7.. +-5-- . -- -3-- -\
| `. | `... -\
| `. .6-- | `... -4-- . - -7..
| | `.
| . .6'- | `. .6--
| .´ |
| ... -4'- .´ | . .6'-
| ...´ - -7'. | .´
+-5'- .´ -/ | ... -4'- .´
| -- -3'- -/ | ...´ - -7'.
| --/ +-5'- .´ -/
| --/ | -- -3'- -/
-2'- -/ | --/
| | --/
| -2'- -/
-1'- |
|
-1'-
In the above chart minuses and slashes represent "real" data amounts, points and In the above chart minuses and slashes represent "real" data amounts, points and
accents represent "useful" data, basically, CEU scaled and cropped output, accents represent "useful" data, basically, CEU scaled and cropped output,
@ -134,6 +138,3 @@ Cropping is performed in the following 6 steps:
5. Calculate and apply host scale = (6' - 6) / (4' - 4) 5. Calculate and apply host scale = (6' - 6) / (4' - 4)
6. Calculate and apply host crop: 6 - 7 = (5 - 2) * (6' - 6) / (5' - 5) 6. Calculate and apply host crop: 6 - 7 = (5 - 2) * (6' - 6) / (5' - 5)
--
Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>