matt
56b9c0b266
- Added CharacterCardV3 struct to handle v3 format - Created From<CharacterCardV3> for CharacterCardV2Data conversion - Updated read_character_card_from_png() to detect and parse both v2 and v3 specs - V3 cards have top-level fields + nested data object - Maintains full backward compatibility with v2 cards - Export still uses v2 format for maximum compatibility
74 lines
2.3 KiB
Python
74 lines
2.3 KiB
Python
#!/usr/bin/env python3
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import struct
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import sys
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def read_png_chunks(filename):
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with open(filename, 'rb') as f:
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# Check PNG signature
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signature = f.read(8)
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if signature != b'\x89PNG\r\n\x1a\n':
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print("Not a valid PNG file!")
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return
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print("Valid PNG file")
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print("\nChunks found:")
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print("-" * 60)
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chunk_num = 0
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while True:
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# Read chunk length
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length_data = f.read(4)
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if len(length_data) < 4:
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break
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length = struct.unpack('>I', length_data)[0]
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# Read chunk type
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chunk_type = f.read(4)
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if len(chunk_type) < 4:
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break
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chunk_type_str = chunk_type.decode('ascii', errors='ignore')
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# Read chunk data
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data = f.read(length)
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# Read CRC
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crc = f.read(4)
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chunk_num += 1
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# Print chunk info
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print(f"{chunk_num}. Type: {chunk_type_str:8s} | Length: {length:8d} bytes", end='')
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# For text chunks, show the keyword
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if chunk_type_str in ['tEXt', 'iTXt', 'zTXt']:
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try:
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# Find null terminator for keyword
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null_pos = data.find(b'\x00')
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if null_pos > 0:
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keyword = data[:null_pos].decode('latin-1', errors='ignore')
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print(f" | Keyword: '{keyword}'", end='')
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# For tEXt, show some of the text content
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if chunk_type_str == 'tEXt' and len(data) > null_pos + 1:
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text_preview = data[null_pos+1:null_pos+51]
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print(f" | Text: {text_preview[:50]}...", end='')
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except:
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pass
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print()
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if chunk_type_str == 'IEND':
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break
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print("-" * 60)
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print(f"Total chunks: {chunk_num}")
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if __name__ == '__main__':
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if len(sys.argv) < 2:
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print("Usage: check_png_chunks.py <png_file>")
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sys.exit(1)
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read_png_chunks(sys.argv[1])
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