✨ AV1 box parsing

Author: mildsunrise

boxes.py

@@ -424,7 +424,32 @@ def parse_hvcC_box(ps: Parser):
 			ps.print(f'    - NALU {n}')
 			print_hex_dump(ps.read(ps.int(2)), ps.prefix + '        ')
 
-# FIXME: implement av1C
+def parse_av1C_box(ps: Parser):
+	with ps.bits(4) as br:
+		ps.reserved('marker', br.bit(), 1)
+		if (version := br.read(7)) != 1:
+			raise AssertionError(f'invalid configuration version: {version}')
+		ps.field('seq_profile', br.read(3))
+		ps.field('seq_level_idx_0', br.read(5))
+		ps.field('seq_tier_0', br.bit())
+		ps.field('high_bitdepth', br.bit())
+		ps.field('twelve_bit', br.bit())
+		ps.field('monochrome', br.bit())
+		ps.field('chroma_subsampling_x', br.bit())
+		ps.field('chroma_subsampling_y', br.bit())
+		ps.field('chroma_sample_position', br.read(2))
+		ps.reserved('reserved', br.read(3))
+
+		if br.bit():
+			ps.field('initial_presentation_delay_minus_one', br.read(4))
+		else:
+			ps.reserved('reserved', br.read(4))
+
+	ps.print('configOBUs =')
+	print_hex_dump(ps.read(), ps.prefix + '  ')
+
+def parse_av1f_box(ps: Parser):
+	ps.field('fwd_distance', ps.int(1))
 
 def parse_esds_box(ps: Parser):
 	parse_fullbox(ps)

tests/lavf-av1.mp4.txt

@@ -52,8 +52,17 @@
                             size = 320 × 240
                             compressorname = 'Lavc60.31.102 libaom-av1'
                             [av1C] AV1CodecConfiguration @ 0x295a, 0x2962 - 0x2975 (19)
-                                81 20 00 00  0a 0d 20 00  00 04 3c ff  bc ff f9 a0   . .... ...<.....
-                                21 a0 04                                             !..
+                                seq_profile = 1
+                                seq_level_idx_0 = 0
+                                seq_tier_0 = False
+                                high_bitdepth = False
+                                twelve_bit = False
+                                monochrome = False
+                                chroma_subsampling_x = False
+                                chroma_subsampling_y = False
+                                chroma_sample_position = 0
+                                configOBUs =
+                                  0a 0d 20 00  00 04 3c ff  bc ff f9 a0  21 a0 04      .. ...<.....!..
                             [fiel] @ 0x2975, 0x297d - 0x297f (2)
                                 01 00                                                ..
                             [pasp] PixelAspectRatio @ 0x297f, 0x2987 - 0x298f (8)