Multiple crops

src/libpisp/backend/backend.cpp

@@ -333,7 +333,16 @@ void BackEnd::GetGamma(pisp_be_gamma_config &gamma)
 
 void BackEnd::SetCrop(pisp_be_crop_config const &crop)
 {
-	be_config_extra_.crop = crop;
+	for (unsigned int i = 0; i < variant_.BackEndNumBranches(0); i++)
+		be_config_extra_.crop[i] = crop;
+	be_config_extra_.dirty_flags_extra |= PISP_BE_DIRTY_CROP;
+	retile_ = true;
+}
+
+void BackEnd::SetCrop(unsigned int i, pisp_be_crop_config const &crop)
+{
+	PISP_ASSERT(i < variant_.BackEndNumBranches(0));
+	be_config_extra_.crop[i] = crop;
 	be_config_extra_.dirty_flags_extra |= PISP_BE_DIRTY_CROP;
 	retile_ = true;
 }

src/libpisp/backend/backend.hpp

@@ -103,6 +103,7 @@ class BackEnd final
 	void SetGamma(pisp_be_gamma_config const &gamma);
 	void GetGamma(pisp_be_gamma_config &gamma);
 	void SetCrop(pisp_be_crop_config const &crop);
+	void SetCrop(unsigned int i, pisp_be_crop_config const &crop);
 	void SetCsc(unsigned int i, pisp_be_ccm_config const &csc);
 	void GetCsc(unsigned int i, pisp_be_ccm_config &csc);
 	void SetOutputFormat(unsigned int i, pisp_be_output_format_config const &output_format);
@@ -155,7 +156,7 @@ class BackEnd final
 		pisp_be_cac_extra cac;
 		pisp_be_downscale_extra downscale[PISP_BACK_END_NUM_OUTPUTS];
 		pisp_be_resample_extra resample[PISP_BACK_END_NUM_OUTPUTS];
-		pisp_be_crop_config crop;
+		pisp_be_crop_config crop[PISP_BACK_END_NUM_OUTPUTS];
 		uint32_t dirty_flags_bayer; //these use pisp_be_bayer_enable
 		uint32_t dirty_flags_rgb; //use pisp_be_rgb_enable
 		uint32_t dirty_flags_extra; //these use pisp_be_dirty_t

src/libpisp/backend/backend_prepare.cpp

@@ -488,9 +488,9 @@ void BackEnd::finaliseConfig()
 		if (enabled)
 		{
 			// crop is enabled when it contains non-zero width/height
-			uint16_t w = be_config_extra_.crop.width ? be_config_extra_.crop.width
+			uint16_t w = be_config_extra_.crop[j].width ? be_config_extra_.crop[j].width
 														: be_config_.input_format.width;
-			uint16_t h = be_config_extra_.crop.width ? be_config_extra_.crop.height
+			uint16_t h = be_config_extra_.crop[j].width ? be_config_extra_.crop[j].height
 														: be_config_.input_format.height;
 
 			if (dirty_flags_rgb & PISP_BE_RGB_ENABLE_DOWNSCALE(j))
@@ -537,18 +537,18 @@ void BackEnd::updateSmartResize()
 {
 	std::string filter;
 
-	// First get the size of the input to the rescalers. The crops are zero when not in use.
-	uint16_t input_width = be_config_extra_.crop.width;
-	if (!input_width)
-		input_width = be_config_.input_format.width;
-	uint16_t input_height = be_config_extra_.crop.height;
-	if (!input_height)
-		input_height = be_config_.input_format.height;
-
 	// Look through the output branches adjusting the scaling blocks where "smart resizing"
 	// has been requested.
 	for (unsigned int i = 0; i < variant_.BackEndNumBranches(0); i++)
 	{
+		// First get the size of the input to the rescalers. The crops are zero when not in use.
+		uint16_t input_width = be_config_extra_.crop[i].width;
+		if (!input_width)
+			input_width = be_config_.input_format.width;
+		uint16_t input_height = be_config_extra_.crop[i].height;
+		if (!input_height)
+			input_height = be_config_.input_format.height;
+
 		if ((smart_resize_dirty_ & (1 << i)) || (be_config_extra_.dirty_flags_extra & PISP_BE_DIRTY_CROP))
 		{
 			if (smart_resize_[i].width && smart_resize_[i].height)
@@ -691,15 +691,16 @@ void BackEnd::updateTiles()
 		PISP_LOG(debug, "Input alignments are " << tiling_config.input_alignment << " pixels");
 
 		tiling_config.input_image_size = tiling::Length2(c.input_format.width, c.input_format.height);
-		tiling_config.crop = tiling::Interval2(tiling::Interval(ce.crop.offset_x, ce.crop.width),
-											   tiling::Interval(ce.crop.offset_y, ce.crop.height));
-
-		if (tiling_config.crop.x.length == 0 || tiling_config.crop.y.length == 0)
-			tiling_config.crop = tiling::Interval2(tiling::Interval(0, c.input_format.width),
-												   tiling::Interval(0, c.input_format.height));
 
 		for (unsigned int i = 0; i < variant_.BackEndNumBranches(0); i++)
 		{
+			tiling_config.crop[i] = tiling::Interval2(tiling::Interval(ce.crop[i].offset_x, ce.crop[i].width),
+													  tiling::Interval(ce.crop[i].offset_y, ce.crop[i].height));
+
+			if (tiling_config.crop[i].x.length == 0 || tiling_config.crop[i].y.length == 0)
+				tiling_config.crop[i] = tiling::Interval2(tiling::Interval(0, c.input_format.width),
+														  tiling::Interval(0, c.input_format.height));
+
 			tiling_config.output_h_mirror[i] = be_config_.output_format[i].transform & PISP_BE_TRANSFORM_HFLIP;
 			tiling_config.downscale_factor[i] =
 				tiling::Length2(c.downscale[i].scale_factor_h, c.downscale[i].scale_factor_v);
@@ -794,25 +795,25 @@ std::vector<pisp_tile> BackEnd::retilePipeline(TilingConfig const &tiling_config
 			}
 
 			tiling::Crop2 downscale_crop;
-			tiling::Interval2 resample_size = tiles[i].crop.output;
+			tiling::Interval2 resample_size = tiles[i].crop[j].output;
 			resample_size.x = resample_size.x - tiles[i].resample[j].crop.x;
 			resample_size.y = resample_size.y - tiles[i].resample[j].crop.y;
 
 			// When a resize stage is disabled, the tile size after the stage is found from the input of the
 			// next block. Also there will be no extra crop necessary for the resize operation.
 			if (be_config_.global.rgb_enables & PISP_BE_RGB_ENABLE_DOWNSCALE(j))
 			{
-				downscale_crop = tiles[i].downscale[j].crop + tiles[i].crop.crop;
+				downscale_crop = tiles[i].downscale[j].crop + tiles[i].crop[j].crop;
 				// Size of the tile going into the resample block needs to be set here.
 				resample_size = tiles[i].downscale[j].output;
 			}
 			else if (be_config_.global.rgb_enables & PISP_BE_RGB_ENABLE_RESAMPLE(j))
 			{
-				downscale_crop = tiles[i].resample[j].crop + tiles[i].crop.crop;
+				downscale_crop = tiles[i].resample[j].crop + tiles[i].crop[j].crop;
 			}
 			else
 			{
-				downscale_crop = tiles[i].output[j].crop + tiles[i].crop.crop;
+				downscale_crop = tiles[i].output[j].crop + tiles[i].crop[j].crop;
 			}
 
 			t.crop_x_start[j] = downscale_crop.x.start;
@@ -952,8 +953,8 @@ void BackEnd::getOutputSize(int i, uint16_t *width, uint16_t *height, pisp_image
 		*width = be_config_extra_.resample[i].scaled_width, *height = be_config_extra_.resample[i].scaled_height;
 	else if (be_config_.global.rgb_enables & PISP_BE_RGB_ENABLE_DOWNSCALE(i))
 		*width = be_config_extra_.downscale[i].scaled_width, *height = be_config_extra_.downscale[i].scaled_height;
-	else if (be_config_extra_.crop.width) // crop width and height will be zero when crop disabled
-		*width = be_config_extra_.crop.width, *height = be_config_extra_.crop.height;
+	else if (be_config_extra_.crop[i].width) // crop width and height will be zero when crop disabled
+		*width = be_config_extra_.crop[i].width, *height = be_config_extra_.crop[i].height;
 	else
 		*width = ifmt.width, *height = ifmt.height;
 }

src/libpisp/backend/tiling/crop_stage.cpp

@@ -12,6 +12,16 @@
 
 using namespace tiling;
 
+namespace
+{
+
+inline bool interval_valid(const Interval &interval, const int min_tile_size)
+{
+	return interval.End() >= min_tile_size && interval.length >= min_tile_size;
+}
+
+} // namespace
+
 CropStage::CropStage(char const *name, Stage *upstream, Config const &config, int struct_offset)
 	: BasicStage(name, upstream->GetPipeline(), upstream, struct_offset), config_(config)
 {
@@ -27,6 +37,11 @@ void CropStage::PushStartUp(int output_start, Dir dir)
 	PISP_LOG(debug, "(" << name_ << ") Enter with output_start " << output_start);
 
 	int input_start = output_start + config_.crop[dir].offset;
+	// input_start can never be negative here, but it is possible to have output_start
+	// negative if, for example, a branch starts producing output on the second
+	// tile in a row (or column) and the resampler requires left (or top) context pixels.
+	if (input_start < 0)
+		throw std::runtime_error("input start is negative: " + std::to_string(input_start));
 	output_interval_.offset = output_start;
 	input_interval_.offset = input_start;
 
@@ -39,11 +54,26 @@ int CropStage::PushEndDown(int input_end, Dir dir)
 	PISP_LOG(debug, "(" << name_ << ") Enter with input_end " << input_end);
 
 	int output_end = input_end - config_.crop[dir].offset;
+
 	if (output_end > config_.crop[dir].length)
 		output_end = config_.crop[dir].length;
-	input_interval_.SetEnd(input_end);
+
 	output_interval_.SetEnd(output_end);
 
+	// If this is the first tile to generate output, ensure we can make at least
+	// min_tile_size of output pixels. If not, terminate iteration here and don't
+	// go futher downstream. Defer the output for the next tile.
+	//
+	// output_end may also be negative if no output will be generated for this tile.
+	if (!interval_valid(output_interval_, GetPipeline()->GetConfig().min_tile_size[dir]))
+	{
+		PISP_LOG(debug, "(" << name_ << ") Output branch not started or output too small, terminating");
+		BasicStage::Reset();
+		return 0;
+	}
+
+	input_interval_.SetEnd(input_end);
+
 	PISP_LOG(debug, "(" << name_ << ") Exit with output_end " << output_end);
 	PushEndUp(downstream_->PushEndDown(output_end, dir), dir);
 	return input_interval_.End();
@@ -57,12 +87,30 @@ void CropStage::PushEndUp(int output_end, Dir dir)
 	input_interval_.SetEnd(input_end);
 	output_interval_.SetEnd(output_end);
 
+	// Same check as we do in PushEndDown().
+	if (!interval_valid(output_interval_, GetPipeline()->GetConfig().min_tile_size[dir]))
+	{
+		PISP_LOG(debug, "(" << name_ << ") Output branch not started or output too small, terminating");
+		BasicStage::Reset();
+		return;
+	}
+
 	PISP_LOG(debug, "(" << name_ << ") Exit with input_end " << input_end);
 }
 
 void CropStage::PushCropDown(Interval interval, Dir dir)
 {
 	PISP_LOG(debug, "(" << name_ << ") Enter with interval " << interval);
+
+	// Branch has not started producing output.  Terminate the iteration here
+	// and don't go futher downstream.
+	if (!interval_valid(output_interval_, GetPipeline()->GetConfig().min_tile_size[dir]))
+	{
+		PISP_LOG(debug, "(" << name_ << ") Output branch not started or output too small, terminating");
+		BasicStage::Reset();
+		return;
+	}
+
 	PISP_ASSERT(interval > input_interval_);
 
 	input_interval_ = interval;
@@ -72,3 +120,8 @@ void CropStage::PushCropDown(Interval interval, Dir dir)
 	PISP_LOG(debug, "(" << name_ << ") Exit with interval " << output_interval_);
 	downstream_->PushCropDown(output_interval_, dir);
 }
+
+bool CropStage::BranchInactive() const
+{
+	return !output_interval_.length;
+}

src/libpisp/backend/tiling/crop_stage.hpp

@@ -20,11 +20,12 @@ class CropStage : public BasicStage
 		Interval2 crop;
 	};
 	CropStage(char const *name, Stage *upstream, Config const &config, int struct_offset);
-	virtual Length2 GetOutputImageSize() const;
-	virtual void PushStartUp(int output_start, Dir dir);
-	virtual int PushEndDown(int input_end, Dir dir);
-	virtual void PushEndUp(int output_end, Dir dir);
-	virtual void PushCropDown(Interval interval, Dir dir);
+	virtual Length2 GetOutputImageSize() const override;
+	virtual void PushStartUp(int output_start, Dir dir) override;
+	virtual int PushEndDown(int input_end, Dir dir) override;
+	virtual void PushEndUp(int output_end, Dir dir) override;
+	virtual void PushCropDown(Interval interval, Dir dir) override;
+	bool BranchInactive() const override;
 
 private:
 	Config config_;

src/libpisp/backend/tiling/output_stage.cpp

@@ -21,7 +21,7 @@ using namespace tiling;
 // the offset/length from the LH edge).
 
 OutputStage::OutputStage(char const *name, Stage *upstream, Config const &config, int struct_offset)
-	: BasicStage(name, upstream->GetPipeline(), upstream, struct_offset), config_(config)
+	: BasicStage(name, upstream->GetPipeline(), upstream, struct_offset), config_(config), branch_complete_(false)
 {
 	pipeline_->AddOutputStage(this);
 }
@@ -118,7 +118,19 @@ void OutputStage::PushCropDown(Interval interval, [[maybe_unused]] Dir dir)
 	PISP_LOG(debug, "(" << name_ << ") Exit with interval " << output_interval_);
 }
 
-bool OutputStage::Done(Dir dir) const
+void OutputStage::Reset()
 {
-	return output_interval_.End() >= GetOutputImageSize()[dir];
+	BasicStage::Reset();
+	branch_complete_ = false;
+}
+
+bool OutputStage::GetBranchComplete() const
+{
+	return branch_complete_;
+}
+
+void OutputStage::SetBranchComplete()
+{
+	branch_complete_ = true;
+	PISP_LOG(debug, "(" << name_ << ") Setting branch complete");
 }

src/libpisp/backend/tiling/output_stage.hpp

@@ -30,10 +30,13 @@ class OutputStage : public BasicStage
 	virtual int PushEndDown(int input_end, Dir dir);
 	virtual void PushEndUp(int output_end, Dir dir);
 	virtual void PushCropDown(Interval interval, Dir dir);
-	bool Done(Dir dir) const;
+	virtual void Reset();
+	bool GetBranchComplete() const;
+	void SetBranchComplete();
 
 private:
 	Config config_;
+	bool branch_complete_;
 };
 
 } // namespace tiling

src/libpisp/backend/tiling/pipeline.cpp

@@ -16,7 +16,7 @@
 
 using namespace tiling;
 
-Pipeline::Pipeline(char const *name, Config const &config) : name_(name), config_(config)
+Pipeline::Pipeline(char const *name, Config const &config) : name_(name), config_(config), first_tile_(false)
 {
 }
 
@@ -74,13 +74,17 @@ int Pipeline::tileDirection(Dir dir, void *mem, size_t num_items, size_t item_si
 	reset();
 	bool done = false;
 	unsigned int num_tiles = 0;
+	first_tile_ = true;
 	for (; !done; num_tiles++)
 	{
 		PISP_LOG(debug, "----------------------------------------------------------------");
 		if (num_tiles == num_items)
 			throw std::runtime_error("Too many tiles!");
 		for (auto s : outputs_)
-			s->PushStartUp(s->GetOutputInterval().End(), dir);
+		{
+			if (!s->BranchComplete())
+				s->PushStartUp(s->GetOutputInterval().End(), dir);
+		}
 		for (auto s : inputs_)
 			s->PushEndDown(s->GetInputInterval().offset + config_.max_tile_size[dir], dir);
 		for (auto s : inputs_)
@@ -90,7 +94,15 @@ int Pipeline::tileDirection(Dir dir, void *mem, size_t num_items, size_t item_si
 			s->CopyOut(dest, dir);
 		done = true;
 		for (auto s : outputs_)
-			done &= s->Done(dir);
+		{
+			if (s->GetBranchComplete())
+				continue;
+			else if (s->GetOutputInterval().End() >= s->GetOutputImageSize()[dir])
+				s->SetBranchComplete();
+			else
+				done = false;
+		}
+		first_tile_ = false;
 	}
 
 	PISP_LOG(debug, "Made " << num_tiles << " tiles in direction " << dir);

src/libpisp/backend/tiling/pipeline.hpp

@@ -37,6 +37,7 @@ class Pipeline
 	void AddInputStage(InputStage *input_stage);
 	void AddOutputStage(OutputStage *output_stage);
 	void Tile(void *mem, size_t num_items, size_t item_size, Length2 *grid);
+	bool FirstTile() const { return first_tile_; }
 
 private:
 	int tileDirection(Dir dir, void *mem, size_t num_items, size_t item_size);
@@ -46,6 +47,7 @@ class Pipeline
 	std::vector<Stage *> stages_;
 	std::vector<InputStage *> inputs_;
 	std::vector<OutputStage *> outputs_;
+	bool first_tile_;
 };
 
 } // namespace tiling

src/libpisp/backend/tiling/pisp_tiling.cpp

@@ -56,11 +56,9 @@ void tile_pipeline(TilingConfig const &config, Tile *tiles, int num_tiles, Lengt
 										Length2(PipelineAlignX, PipelineAlignY));
 	ContextStage context_stage("context", &input_stage, context_config, offsetof(Tile, context));
 
-	CropStage::Config crop_config(config.crop);
-	CropStage crop_stage("crop", &context_stage, crop_config, offsetof(Tile, crop));
-
-	SplitStage split_stage("split", &crop_stage);
+	SplitStage split_stage("split", &context_stage);
 
+	std::unique_ptr<Stage> crop_stages[NumOutputBranches];
 	std::unique_ptr<Stage> downscale_stages[NumOutputBranches];
 	std::unique_ptr<Stage> resample_stages[NumOutputBranches];
 	std::unique_ptr<Stage> output_stages[NumOutputBranches];
@@ -74,6 +72,11 @@ void tile_pipeline(TilingConfig const &config, Tile *tiles, int num_tiles, Lengt
 		char name[32];
 		Stage *prev_stage = &split_stage;
 
+		sprintf(name, "crop%d", i);
+		crop_stages[i] = std::unique_ptr<Stage>(
+			new CropStage(name, prev_stage, config.crop[i], offsetof(Tile, crop) + i * sizeof(Region)));
+		prev_stage = crop_stages[i].get();
+
 		// There's a little awkwardness if the resize blocks (downscale and resample) are not enabled. Resize *does* change the output tile
 		// size, even if it's doing a 1-to-1 scaling (it loses context), so we must leave it out of the tiling
 		// calculation.