Diffstat (limited to 'patches/0003-ipa-simple-data-add-ov02c10-tuning-file.patch')
| -rw-r--r-- | patches/0003-ipa-simple-data-add-ov02c10-tuning-file.patch | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/patches/0003-ipa-simple-data-add-ov02c10-tuning-file.patch b/patches/0003-ipa-simple-data-add-ov02c10-tuning-file.patch new file mode 100644 index 0000000..24f2143 --- /dev/null +++ b/patches/0003-ipa-simple-data-add-ov02c10-tuning-file.patch @@ -0,0 +1,78 @@ +ipa: simple: data: Add an OV02C10 tuning file + +The simple IPA applies a colour correction matrix only when the tuning file +asks for it, and there is no tuning file for the OV02C10, so the front camera +of the Surface Pro 12in falls back to uncalibrated.yaml: + + WARN IPAProxy ipa_proxy.cpp:196 Configuration file 'ov02c10.yaml' not found for IPA module 'simple', falling back to '/usr/share/libcamera/ipa/simple/uncalibrated.yaml' + +That leaves the CCM at identity, i.e. the raw sensor channels are displayed as +if they were sRGB. The grey-world AWB does balance the frame, so the preview is +not tinted on average -- captured through PipeWire on this board it measures +R/G 1.03 and B/G 0.98 -- but it is flat: mean HSV saturation 0.07, with 94% of +the pixels below 0.15. Skin therefore lands close to grey and reads cyan. + +Add a tuning file that enables Ccm with a hand-tuned matrix whose blue row sums +to 0.85, both to restore saturation and to take the cool edge off what the +grey-world AWB leaves behind. It is not lab-calibrated, and the file says so. + +--- /dev/null ++++ b/src/ipa/simple/data/ov02c10.yaml +@@ -0,0 +1,47 @@ ++# SPDX-License-Identifier: CC0-1.0 ++# ++# Software ISP tuning for the OV02C10 front camera of the Microsoft Surface ++# Pro 12in. ++# ++# With no tuning file the simple IPA falls back to uncalibrated.yaml, which ++# runs no CCM: the raw sensor channels are handed to the display as though they ++# were already sRGB. The grey-world AWB still balances the frame on average, so ++# the preview is not tinted overall -- measured on this board its mean channel ++# ratios are R/G 1.03 and B/G 0.98 -- it is flat, with a mean HSV saturation of ++# 0.07 and 94% of the pixels below 0.15. What little colour survives reads ++# cool, and that is what makes skin look cyan. ++# ++# The matrix below is hand-tuned, not measured against a colour target. Its ++# off-diagonal terms undo part of the CFA crosstalk and so restore saturation, ++# and its blue row sums to 0.85 rather than 1.0, taking 15% out of blue to ++# counter the cool cast the grey-world AWB leaves behind. It comes from the ++# Samsung Galaxy Book OV02C10 work, which met the same sensor on the same ++# software ISP: ++# ++# https://github.com/hfb0/galaxy-book-ipu6-ov02c10-linux ++# ++# Both entries carry the same matrix, so nothing is interpolated over colour ++# temperature. There is no measured data to justify two different ones. ++# ++# The black level is deliberately not repeated here. The CameraSensorHelper ++# added by 0001-libipa-camera_sensor-add-ov02c10.patch already reports 0x40 at ++# 10 bits, which is what a dark frame off the CAMSS RDI node measures, and one ++# source for it is enough. ++# ++# Enabling Ccm also exposes the Saturation control, and costs nothing ++# noticeable here because the software ISP debayers on the GPU. ++%YAML 1.1 ++--- ++version: 1 ++algorithms: ++ - BlackLevel: ++ - Awb: ++ - Ccm: ++ ccms: ++ - ct: 2860 ++ ccm: [ 1.35, -0.20, -0.15, -0.15, 1.30, -0.15, -0.05, -0.20, 1.10 ] ++ - ct: 6500 ++ ccm: [ 1.35, -0.20, -0.15, -0.15, 1.30, -0.15, -0.05, -0.20, 1.10 ] ++ - Adjust: ++ - Agc: ++... +--- a/src/ipa/simple/data/meson.build ++++ b/src/ipa/simple/data/meson.build +@@ -1,6 +1,7 @@ + # SPDX-License-Identifier: CC0-1.0 + + conf_files = files([ ++ 'ov02c10.yaml', + 'uncalibrated.yaml', + ]) + |