From patchwork Sat Apr 25 00:45:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 3538 Return-Path: Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id C782E62E45 for ; Sat, 25 Apr 2020 02:45:53 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="VgjGHQZZ"; dkim-atps=neutral Received: from pendragon.bb.dnainternet.fi (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 4D49E4F7; Sat, 25 Apr 2020 02:45:53 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1587775553; bh=2hq6nSqBeXPY+gKPtrw3F1EgXjYPCWQB3Wf8fmoaKrQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VgjGHQZZ2ufQaiEOtDG/KHAtiQ3o7uj4TyVgH4CkVvA0z9ixqF0tHy6J0Ti5AJ89i IoTikoSq9iHNYnJ/prlCpTyCgkqP/I53P9thnYSSUXT5phuFAbbAsSWCsZNoQhTEyl Behl5nkcNWh2+qgDsz9/h/lKaYvONpHcWGRXO4+A= From: Laurent Pinchart To: libcamera-devel@lists.libcamera.org Date: Sat, 25 Apr 2020 03:45:30 +0300 Message-Id: <20200425004533.26907-5-laurent.pinchart@ideasonboard.com> X-Mailer: git-send-email 2.25.3 In-Reply-To: <20200425004533.26907-1-laurent.pinchart@ideasonboard.com> References: <20200425004533.26907-1-laurent.pinchart@ideasonboard.com> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v5 4/7] libcamera: controls: Updates to gain and exposure controls X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 25 Apr 2020 00:45:55 -0000 From: Naushir Patuck Rename: ManualExposure -> ExposureTime ManualGain -> AnalogueGain Use micro-seconds units for ExposureTime. This is changed from milli- seconds. The latter would not allow very low exposure times. AnalogueGain switch to use a float to allow fractional gain adjustments. Update the uvcvideo pipeline handler to use the new exposure and gain units. For ExposureTime, UVC uses units of 100 micro-seconds, so map the values before setting V4L2_CID_EXPOSURE_ABSOLUTE. For AnalogueGain, UVC has no explicit gain units, so map the default gain value to 1.0 and linearly scale to the requested value. Signed-off-by: Naushir Patuck Reviewed-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/libcamera/control_ids.yaml | 22 ++++-- src/libcamera/pipeline/uvcvideo/uvcvideo.cpp | 77 +++++++++++++++++++- 2 files changed, 87 insertions(+), 12 deletions(-) diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml index bcbab195a374..d8bdb3829be4 100644 --- a/src/libcamera/control_ids.yaml +++ b/src/libcamera/control_ids.yaml @@ -12,7 +12,7 @@ controls: description: | Enable or disable the AE. - \sa ManualExposure + \sa ExposureTime AnalogueGain - AeLocked: type: bool @@ -30,8 +30,6 @@ controls: description: | Enable or disable the AWB. - \sa ManualGain - - Brightness: type: int32_t description: Specify a fixed brightness parameter @@ -44,12 +42,20 @@ controls: type: int32_t description: Specify a fixed saturation parameter - - ManualExposure: + - ExposureTime: type: int32_t - description: Specify a fixed exposure time in milli-seconds + description: | + Exposure time (shutter speed) for the frame applied in the sensor + device. This value is specified in micro-seconds. - - ManualGain: - type: int32_t - description: Specify a fixed gain parameter + \sa AnalogueGain AeEnable + + - AnalogueGain: + type: float + description: | + Analogue gain value applied in the sensor device. + The value of the control specifies the gain multiplier applied to all + colour channels. This value cannot be lower than 1.0. + \sa ExposureTime AeEnable ... diff --git a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp index b040f2460b1c..452f38dcad2f 100644 --- a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp +++ b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp @@ -254,13 +254,19 @@ 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() @@ -270,6 +276,28 @@ int PipelineHandlerUVC::processControl(ControlList *controls, unsigned int id, break; } + case V4L2_CID_EXPOSURE_ABSOLUTE: + controls->set(cid, value.get() / 100); + break; + + case V4L2_CID_GAIN: { + int32_t min = v4l2Info.min().get(); + int32_t max = v4l2Info.max().get(); + int32_t def = v4l2Info.def().get(); + + 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() - p) / m; + controls->set(cid, static_cast(lroundf(fvalue))); + break; + } + default: { int32_t ivalue = value.get(); controls->set(cid, ivalue); @@ -413,21 +441,62 @@ 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 max = v4l2Info.max().get(); + int32_t def = v4l2Info.def().get(); + 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;