LibGfx/JPEG2000: Support "segmentation symbols" code block style

Author: nico

Tests/LibGfx/TestImageDecoder.cpp

@@ -697,6 +697,7 @@ TEST_CASE(test_jpeg2000_decode)
         TEST_INPUT("jpeg2000/openjpeg-lossless-rgba-u8-prog0-tile3x2-cblk4x16-tp3-layers3-res2-mct.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-02-resetprob.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-08-vcausal.jp2"sv),
+        TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-32-segsym.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-tile3x2-res5.jp2"sv),
         TEST_INPUT("jpeg2000/openjpeg-lossless-rgba-u8-prog0-SOP.jp2"sv),
         TEST_INPUT("jpeg2000/openjpeg-lossless-rgba-u8-prog0-EPH.jp2"sv),
@@ -789,7 +790,6 @@ TEST_CASE(test_jpeg2000_decode_unsupported)
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-01-bypass.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-04-termall.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-16-pterm.jp2"sv),
-        TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-32-segsym.jp2"sv),
         TEST_INPUT("jpeg2000/jasper-rgba-u8-cbstyle-63-all.jp2"sv),
         TEST_INPUT("jpeg2000/kakadu-lossless-cmyk-u8-prog1-layers1-res6.jp2"sv),
         TEST_INPUT("jpeg2000/kakadu-lossless-cmyka-u8-prog1-layers1-res6.jp2"sv),

Userland/Libraries/LibGfx/ImageFormats/JPEG2000BitplaneDecoding.h

@@ -16,6 +16,7 @@ namespace Gfx::JPEG2000 {
 struct BitplaneDecodingOptions {
     bool reset_context_probabilities_each_pass { false };
     bool uses_vertically_causal_context { false };
+    bool uses_segmentation_symbols { false };
 };
 
 inline ErrorOr<void> decode_code_block(Span2D<i16> result, SubBand sub_band, int number_of_coding_passes, ReadonlyBytes data, int M_b, int p, BitplaneDecodingOptions options = {})
@@ -466,6 +467,17 @@ inline ErrorOr<void> decode_code_block(Span2D<i16> result, SubBand sub_band, int
             break;
         case 2:
             cleanup_pass(current_bitplane, pass);
+
+            if (options.uses_segmentation_symbols) {
+                // D.5 Error resilience segmentation symbol
+                u8 segmentation_symbol = arithmetic_decoder.get_next_bit(uniform_context);
+                segmentation_symbol = (segmentation_symbol << 1) | arithmetic_decoder.get_next_bit(uniform_context);
+                segmentation_symbol = (segmentation_symbol << 1) | arithmetic_decoder.get_next_bit(uniform_context);
+                segmentation_symbol = (segmentation_symbol << 1) | arithmetic_decoder.get_next_bit(uniform_context);
+                if (segmentation_symbol != 0xA)
+                    return Error::from_string_literal("JPEG2000ImageDecoderPlugin: Invalid segmentation symbol");
+            }
+
             ++current_bitplane;
             break;
         }

Userland/Libraries/LibGfx/ImageFormats/JPEG2000Loader.cpp

@@ -1474,7 +1474,7 @@ static ErrorOr<u32> read_one_packet_header(JPEG2000LoadingContext& context, Tile
     u32 const current_layer_index = progression_data.layer;
 
     // FIXME: Relax. Will need implementing D.5, D.6, D.7, and probably more.
-    if ((coding_parameters.code_block_style & ~(8 | 2)) != 0)
+    if ((coding_parameters.code_block_style & ~(0x20 | 8 | 2)) != 0)
         return Error::from_string_literal("JPEG2000ImageDecoderPlugin: Code-block style not yet implemented");
 
     // B.10 Packet header information coding
@@ -1822,6 +1822,7 @@ static ErrorOr<void> decode_bitplanes_to_coefficients(JPEG2000LoadingContext& co
         JPEG2000::BitplaneDecodingOptions bitplane_decoding_options;
         bitplane_decoding_options.reset_context_probabilities_each_pass = coding_style.reset_context_probabilities();
         bitplane_decoding_options.uses_vertically_causal_context = coding_style.uses_vertically_causal_context();
+        bitplane_decoding_options.uses_segmentation_symbols = coding_style.uses_segmentation_symbols();
 
         int M_b = compute_M_b(context, tile, component_index, sub_band_type, r, N_L);