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VGMParse support for versions 1.00, 1.01 and 1.10
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@rejunity
rejunity committed Nov 7, 2023
1 parent 5fc7f11 commit 658f80e
Showing 1 changed file with 83 additions and 28 deletions.
111 changes: 83 additions & 28 deletions src/vgmparse.py
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Original file line number Diff line number Diff line change
Expand Up @@ -11,13 +11,18 @@
class VersionError(Exception):
pass


#
# VGM Specification: https://vgmrips.net/wiki/VGM_Specification
#
class Parser:
# VGM file identifier
vgm_magic_number = b'Vgm '

# Supported VGM versions
supported_ver_list = [
0x00000100,
0x00000101,
0x00000110,
0x00000150,
0x00000151,
0x00000160,
Expand All @@ -28,6 +33,58 @@ class Parser:

# VGM metadata offsets
metadata_offsets = {
# Version 1.00
0x00000100: {
'vgm_ident': {'offset': 0x00, 'size': 4, 'type_format': None},
'eof_offset': {'offset': 0x04, 'size': 4, 'type_format': '<I'},
'version': {'offset': 0x08, 'size': 4, 'type_format': '<I'},
'sn76489_clock': {'offset': 0x0c, 'size': 4, 'type_format': '<I'},
# 1.00/1.01 specific - later ym2413_clock
'ym2151_clock': {'offset': 0x10, 'size': 4, 'type_format': '<I', 'condition': lambda val: val <= 5000000},
# 1.00/1.01 specific - later ym2413_clock
'ym2612_clock': {'offset': 0x10, 'size': 4, 'type_format': '<I', 'condition': lambda val: val > 5000000 },
'gd3_offset': {'offset': 0x14, 'size': 4, 'type_format': '<I'},
'total_samples': {'offset': 0x18, 'size': 4, 'type_format': '<I'},
'loop_offset': {'offset': 0x1c, 'size': 4, 'type_format': '<I'},
'loop_samples': {'offset': 0x20, 'size': 4, 'type_format': '<I'},
'sn76489_feedback': 0x0009,
'sn76489_shift_register_width': 16,
},
# Version 1.01
0x00000101: {
'vgm_ident': {'offset': 0x00, 'size': 4, 'type_format': None},
'eof_offset': {'offset': 0x04, 'size': 4, 'type_format': '<I'},
'version': {'offset': 0x08, 'size': 4, 'type_format': '<I'},
'sn76489_clock': {'offset': 0x0c, 'size': 4, 'type_format': '<I'},
# 1.00/1.01 specific - later ym2413_clock
'ym2151_clock': {'offset': 0x10, 'size': 4, 'type_format': '<I', 'condition': lambda val: val <= 5000000},
# 1.00/1.01 specific - later ym2413_clock
'ym2612_clock': {'offset': 0x10, 'size': 4, 'type_format': '<I', 'condition': lambda val: val > 5000000 },
'gd3_offset': {'offset': 0x14, 'size': 4, 'type_format': '<I'},
'total_samples': {'offset': 0x18, 'size': 4, 'type_format': '<I'},
'loop_offset': {'offset': 0x1c, 'size': 4, 'type_format': '<I'},
'loop_samples': {'offset': 0x20, 'size': 4, 'type_format': '<I'},
'rate': {'offset': 0x24, 'size': 4, 'type_format': '<I'}, # 1.01
'sn76489_feedback': 0x0009,
'sn76489_shift_register_width': 16,
},
# Version 1.10
0x00000110: {
'vgm_ident': {'offset': 0x00, 'size': 4, 'type_format': None},
'eof_offset': {'offset': 0x04, 'size': 4, 'type_format': '<I'},
'version': {'offset': 0x08, 'size': 4, 'type_format': '<I'},
'sn76489_clock': {'offset': 0x0c, 'size': 4, 'type_format': '<I'},
'ym2413_clock': {'offset': 0x10, 'size': 4, 'type_format': '<I'},
'gd3_offset': {'offset': 0x14, 'size': 4, 'type_format': '<I'},
'total_samples': {'offset': 0x18, 'size': 4, 'type_format': '<I'},
'loop_offset': {'offset': 0x1c, 'size': 4, 'type_format': '<I'},
'loop_samples': {'offset': 0x20, 'size': 4, 'type_format': '<I'},
'rate': {'offset': 0x24, 'size': 4, 'type_format': '<I'},
'sn76489_feedback': {'offset': 0x28, 'size': 2, 'type_format': '<H'}, # 1.10
'sn76489_shift_register_width': {'offset': 0x2a, 'size': 1, 'type_format': 'B'}, #1.10
'ym2612_clock': {'offset': 0x2c, 'size': 4, 'type_format': '<I'}, # 1.10
'ym2151_clock': {'offset': 0x30, 'size': 4, 'type_format': '<I'}, # 1.10
},
# Version 1.50
0x00000150: {
'vgm_ident': {'offset': 0x00, 'size': 4, 'type_format': None},
Expand All @@ -40,23 +97,11 @@ class Parser:
'loop_offset': {'offset': 0x1c, 'size': 4, 'type_format': '<I'},
'loop_samples': {'offset': 0x20, 'size': 4, 'type_format': '<I'},
'rate': {'offset': 0x24, 'size': 4, 'type_format': '<I'},
'sn76489_feedback': {
'offset': 0x28,
'size': 2,
'type_format': '<H',
},
'sn76489_shift_register_width': {
'offset': 0x2a,
'size': 1,
'type_format': 'B',
},
'sn76489_feedback': {'offset': 0x28, 'size': 2, 'type_format': '<H'},
'sn76489_shift_register_width': {'offset': 0x2a,'size': 1,'type_format': 'B'},
'ym2612_clock': {'offset': 0x2c, 'size': 4, 'type_format': '<I'},
'ym2151_clock': {'offset': 0x30, 'size': 4, 'type_format': '<I'},
'vgm_data_offset': {
'offset': 0x34,
'size': 4,
'type_format': '<I',
},
'vgm_data_offset': {'offset': 0x34, 'size': 4, 'type_format': '<I'}, # 1.50
},
# Version 1.51
0x00000151: {
Expand Down Expand Up @@ -336,6 +381,7 @@ def __init__(self, vgm_data):
self.validate_vgm_data()

# Set up the variables that will be populated
self.vgm_data_offset = 0x40
self.command_list = []
self.data_block = None
self.data_block_type = None
Expand All @@ -356,8 +402,9 @@ def parse_commands(self):

# Seek to the start of the VGM data
self.data.seek(
self.metadata['vgm_data_offset'] +
self.metadata_offsets[self.metadata['version']]['vgm_data_offset']['offset']
self.vgm_data_offset
#self.metadata['vgm_data_offset'] +
#self.metadata_offsets[self.metadata['version']]['vgm_data_offset']['offset']
)

while True:
Expand Down Expand Up @@ -628,15 +675,18 @@ def parse_metadata(self):
for version, offsets in self.metadata_offsets.items():
# Skip parsing metadata from VGM versions later than the version of the file
if version <= self.metadata.get('version', highest_supported_version):

# Calculate offset of VGM data
if 'vgm_data_offset' in self.metadata:
self.vgm_data_offset = self.metadata['vgm_data_offset'] + \
self.metadata_offsets[version]['vgm_data_offset']['offset']
header_end = self.vgm_data_offset # Header ends where VGM data starts

for value, offset_data in offsets.items():

# Calculate offset of VGM data
vgm_data_offset = self.metadata.get('vgm_data_offset', 0)
if vgm_data_offset > 0:
vgm_data_offset += self.metadata_offsets[version]['vgm_data_offset']['offset']
else:
vgm_data_offset = 0x40
header_end = vgm_data_offset # Header ends where VGM data starts
if not isinstance(offset_data, dict):
self.metadata[value] = offset_data
continue

# Skip parsing metadata attributes that are located outside the header,
# set them to 0 instead.
Expand All @@ -655,12 +705,17 @@ def parse_metadata(self):

# Unpack the data if required
if offset_data['type_format'] is not None:
self.metadata[value] = struct.unpack(
data = struct.unpack(
offset_data['type_format'],
data,
)[0]
else:
self.metadata[value] = data

# Check if special condition applies
# mostly used for a backwards compatibility handling in pre 1.10 formats
if 'condition' in offset_data and not offset_data['condition'](data):
continue

self.metadata[value] = data

# Seek back to the original position in the VGM data
self.data.seek(original_pos)
Expand Down

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