libcamera: Use utils::abs_diff()

Use the new utils::abs_diff() function where appropriate to replace
manual implementations.

While at it fix a header ordering issue in
src/libcamera/pipeline/raspberrypi/raspberrypi.cpp.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>

src/ipa/ipu3/algorithms/agc.cpp

@@ -12,6 +12,7 @@
 #include <cmath>
 
 #include <libcamera/base/log.h>
+#include <libcamera/base/utils.h>
 
 #include <libcamera/ipa/core_ipa_interface.h>
 
@@ -188,7 +189,7 @@ void Agc::computeExposure(IPAFrameContext &frameContext, double yGain,
 	double evGain = std::max(yGain, iqMeanGain);
 
 	/* Consider within 1% of the target as correctly exposed */
-	if (std::abs(evGain - 1.0) < 0.01)
+	if (utils::abs_diff(evGain, 1.0) < 0.01)
 		LOG(IPU3Agc, Debug) << "We are well exposed (evGain = "
 				    << evGain << ")";
 

src/ipa/ipu3/ipu3.cpp

@@ -354,7 +354,7 @@ void IPAIPU3::calculateBdsGrid(const Size &bdsOutputSize)
 					    kMaxGridWidth);
 
 		width = width << shift;
-		uint32_t error = std::abs(static_cast<int>(width - bdsOutputSize.width));
+		uint32_t error = utils::abs_diff(width, bdsOutputSize.width);
 		if (error >= minError)
 			continue;
 
@@ -370,7 +370,7 @@ void IPAIPU3::calculateBdsGrid(const Size &bdsOutputSize)
 					     kMaxGridHeight);
 
 		height = height << shift;
-		uint32_t error = std::abs(static_cast<int>(height - bdsOutputSize.height));
+		uint32_t error = utils::abs_diff(height, bdsOutputSize.height);
 		if (error >= minError)
 			continue;
 

src/ipa/rkisp1/algorithms/agc.cpp

@@ -12,6 +12,7 @@
 #include <cmath>
 
 #include <libcamera/base/log.h>
+#include <libcamera/base/utils.h>
 
 #include <libcamera/ipa/core_ipa_interface.h>
 
@@ -145,7 +146,7 @@ void Agc::computeExposure(IPAContext &context, double yGain)
 					  kMaxAnalogueGain);
 
 	/* Consider within 1% of the target as correctly exposed. */
-	if (std::abs(yGain - 1.0) < 0.01)
+	if (utils::abs_diff(yGain, 1.0) < 0.01)
 		return;
 
 	/* extracted from Rpi::Agc::computeTargetExposure. */

src/libcamera/pipeline/ipu3/imgu.cpp

@@ -81,7 +81,7 @@ float findScaleFactor(float sf, const std::vector<float> &range,
 	float bestDiff = std::numeric_limits<float>::max();
 	unsigned int index = 0;
 	for (unsigned int i = 0; i < range.size(); ++i) {
-		float diff = std::abs(sf - range[i]);
+		float diff = utils::abs_diff(sf, range[i]);
 		if (diff < bestDiff) {
 			bestDiff = diff;
 			index = i;
@@ -99,7 +99,7 @@ bool isSameRatio(const Size &in, const Size &out)
 	float inRatio = static_cast<float>(in.width) / in.height;
 	float outRatio = static_cast<float>(out.width) / out.height;
 
-	if (std::abs(inRatio - outRatio) > 0.1)
+	if (utils::abs_diff(inRatio, outRatio) > 0.1)
 		return false;
 
 	return true;

src/libcamera/pipeline/raspberrypi/raspberrypi.cpp

@@ -14,6 +14,7 @@
 #include <unordered_set>
 
 #include <libcamera/base/shared_fd.h>
+#include <libcamera/base/utils.h>
 
 #include <libcamera/camera.h>
 #include <libcamera/control_ids.h>
@@ -25,8 +26,6 @@
 #include <libcamera/property_ids.h>
 #include <libcamera/request.h>
 
-#include <libcamera/base/utils.h>
-
 #include <linux/bcm2835-isp.h>
 #include <linux/media-bus-format.h>
 #include <linux/videodev2.h>
@@ -154,7 +153,7 @@ V4L2SubdeviceFormat findBestFormat(const SensorFormats &formatsMap, const Size &
 			score += penaltyAr * scoreFormat(reqAr, fmtAr);
 
 			/* Add any penalties... this is not an exact science! */
-			score += std::abs(static_cast<int>(info.bitsPerPixel - bitDepth)) * penaltyBitDepth;
+			score += utils::abs_diff(info.bitsPerPixel, bitDepth) * penaltyBitDepth;
 
 			if (score <= bestScore) {
 				bestScore = score;