1 files changed, 47 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/dec_group_border.h b/third_party/jpeg-xl/lib/jxl/dec_group_border.h
new file mode 100644
index 0000000000..2d974c9987
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/dec_group_border.h
@@ -0,0 +1,47 @@
+// Copyright (c) the JPEG XL Project Authors. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#ifndef LIB_JXL_DEC_GROUP_BORDER_H_
+#define LIB_JXL_DEC_GROUP_BORDER_H_
+
+#include <stddef.h>
+
+#include <atomic>
+
+#include "lib/jxl/base/arch_macros.h"
+#include "lib/jxl/base/status.h"
+#include "lib/jxl/common.h"
+#include "lib/jxl/image.h"
+
+namespace jxl {
+
+class GroupBorderAssigner {
+ public:
+  // Prepare the GroupBorderAssigner to handle a given frame.
+  void Init(const FrameDimensions& frame_dim);
+  // Marks a group as done, and returns the (at most 3) rects to run
+  // FinalizeImageRect on. `block_rect` must be the rect corresponding
+  // to the given `group_id`, measured in blocks.
+  void GroupDone(size_t group_id, size_t padx, size_t pady,
+                 Rect* rects_to_finalize, size_t* num_to_finalize);
+  // Marks a group as not-done, for running re-paints.
+  void ClearDone(size_t group_id);
+
+  static constexpr size_t kMaxToFinalize = 3;
+
+ private:
+  FrameDimensions frame_dim_;
+  std::unique_ptr<std::atomic<uint8_t>[]> counters_;
+
+  // Constants to identify group positions relative to the corners.
+  static constexpr uint8_t kTopLeft = 0x01;
+  static constexpr uint8_t kTopRight = 0x02;
+  static constexpr uint8_t kBottomRight = 0x04;
+  static constexpr uint8_t kBottomLeft = 0x08;
+};
+
+}  // namespace jxl
+
+#endif  // LIB_JXL_DEC_GROUP_BORDER_H_