diff options
Diffstat (limited to 'src/libcamera/pipeline/uvcvideo/uvcvideo.cpp')
| -rw-r--r-- | src/libcamera/pipeline/uvcvideo/uvcvideo.cpp | 78 |
1 files changed, 74 insertions, 4 deletions
diff --git a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp index b040f246..08462542 100644 --- a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp +++ b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp @@ -7,6 +7,7 @@ #include <algorithm> #include <iomanip> +#include <math.h> #include <sys/sysmacros.h> #include <tuple> @@ -254,13 +255,19 @@ int PipelineHandlerUVC::processControl(ControlList *controls, unsigned int id, cid = V4L2_CID_SATURATION; else if (id == controls::AeEnable) cid = V4L2_CID_EXPOSURE_AUTO; - else if (id == controls::ManualExposure) + else if (id == controls::ExposureTime) cid = V4L2_CID_EXPOSURE_ABSOLUTE; - else if (id == controls::ManualGain) + else if (id == controls::AnalogueGain) cid = V4L2_CID_GAIN; else return -EINVAL; + const ControlInfo &v4l2Info = controls->infoMap()->at(cid); + + /* + * See UVCCameraData::addControl() for explanations of the different + * value mappings. + */ switch (cid) { case V4L2_CID_EXPOSURE_AUTO: { int32_t ivalue = value.get<bool>() @@ -270,6 +277,28 @@ int PipelineHandlerUVC::processControl(ControlList *controls, unsigned int id, break; } + case V4L2_CID_EXPOSURE_ABSOLUTE: + controls->set(cid, value.get<int32_t>() / 100); + break; + + case V4L2_CID_GAIN: { + int32_t min = v4l2Info.min().get<int32_t>(); + int32_t max = v4l2Info.max().get<int32_t>(); + int32_t def = v4l2Info.def().get<int32_t>(); + + float m = (4.0f - 1.0f) / (max - def); + float p = 1.0f - m * def; + + if (m * min + p < 0.5f) { + m = (1.0f - 0.5f) / (def - min); + p = 1.0f - m * def; + } + + float fvalue = (value.get<float>() - p) / m; + controls->set(cid, static_cast<int32_t>(lroundf(fvalue))); + break; + } + default: { int32_t ivalue = value.get<int32_t>(); controls->set(cid, ivalue); @@ -413,21 +442,62 @@ void UVCCameraData::addControl(uint32_t cid, const ControlInfo &v4l2Info, id = &controls::AeEnable; break; case V4L2_CID_EXPOSURE_ABSOLUTE: - id = &controls::ManualExposure; + id = &controls::ExposureTime; break; case V4L2_CID_GAIN: - id = &controls::ManualGain; + id = &controls::AnalogueGain; break; default: return; } /* Map the control info. */ + int32_t min = v4l2Info.min().get<int32_t>(); + int32_t max = v4l2Info.max().get<int32_t>(); + int32_t def = v4l2Info.def().get<int32_t>(); + switch (cid) { case V4L2_CID_EXPOSURE_AUTO: info = ControlInfo{ false, true, true }; break; + case V4L2_CID_EXPOSURE_ABSOLUTE: + /* + * ExposureTime is in units of 1 µs, and UVC expects + * V4L2_CID_EXPOSURE_ABSOLUTE in units of 100 µs. + */ + info = ControlInfo{ + { min * 100 }, + { max * 100 }, + { def * 100 } + }; + break; + + case V4L2_CID_GAIN: { + /* + * The AnalogueGain control is a float, with 1.0 mapped to the + * default value. UVC doesn't specify units, and cameras have + * been seen to expose very different ranges for the gain + * control. Arbitrarily assume that the minimum and maximum + * values are respectively no lower than 0.5 and no higher than + * 4.0. + */ + float m = (4.0f - 1.0f) / (max - def); + float p = 1.0f - m * def; + + if (m * min + p < 0.5f) { + m = (1.0f - 0.5f) / (def - min); + p = 1.0f - m * def; + } + + info = ControlInfo{ + { m * min + p }, + { m * max + p }, + { 1.0f } + }; + break; + } + default: info = v4l2Info; break; |