π FileMgr
π
/
lib64
/
python3.9
/
__pycache__
βοΈ /
β¬ Kembali
a οΏ½i; οΏ½ @ s d Z G ddοΏ½ dοΏ½ZdS )a Simple class to read IFF chunks. An IFF chunk (used in formats such as AIFF, TIFF, RMFF (RealMedia File Format)) has the following structure: +----------------+ | ID (4 bytes) | +----------------+ | size (4 bytes) | +----------------+ | data | | ... | +----------------+ The ID is a 4-byte string which identifies the type of chunk. The size field (a 32-bit value, encoded using big-endian byte order) gives the size of the whole chunk, including the 8-byte header. Usually an IFF-type file consists of one or more chunks. The proposed usage of the Chunk class defined here is to instantiate an instance at the start of each chunk and read from the instance until it reaches the end, after which a new instance can be instantiated. At the end of the file, creating a new instance will fail with an EOFError exception. Usage: while True: try: chunk = Chunk(file) except EOFError: break chunktype = chunk.getname() while True: data = chunk.read(nbytes) if not data: pass # do something with data The interface is file-like. The implemented methods are: read, close, seek, tell, isatty. Extra methods are: skip() (called by close, skips to the end of the chunk), getname() (returns the name (ID) of the chunk) The __init__ method has one required argument, a file-like object (including a chunk instance), and one optional argument, a flag which specifies whether or not chunks are aligned on 2-byte boundaries. The default is 1, i.e. aligned. c @ sZ e Zd ZdddοΏ½ZddοΏ½ ZddοΏ½ Zd d οΏ½ ZddοΏ½ ZdddοΏ½ZddοΏ½ Z dddοΏ½Z ddοΏ½ ZdS )οΏ½ChunkTFc C sοΏ½ dd l }d| _|| _|rd}nd}|| _|οΏ½dοΏ½| _t| jοΏ½dk rFtοΏ½z |οΏ½|d |οΏ½dοΏ½οΏ½d | _ W n |j yοΏ½ td οΏ½Y n0 |rοΏ½| j d | _ d| _z| jοΏ½οΏ½ | _ W n ttfyοΏ½ d| _Y n0 d| _d S ) NοΏ½ FοΏ½>οΏ½<οΏ½ οΏ½LοΏ½ T)οΏ½structοΏ½closedοΏ½alignοΏ½fileοΏ½readοΏ½ chunknameοΏ½lenοΏ½EOFErrorοΏ½unpack_fromοΏ½ chunksizeοΏ½errorοΏ½ size_readοΏ½tellοΏ½offsetοΏ½AttributeErrorοΏ½OSErrorοΏ½seekable)οΏ½selfr r Z bigendianZ inclheaderr ZstrflagοΏ½ r οΏ½/usr/lib64/python3.9/chunk.pyοΏ½__init__4 s, zChunk.__init__c C s | j S )z*Return the name (ID) of the current chunk.)r οΏ½r r r r οΏ½getnameN s z Chunk.getnamec C s | j S )z%Return the size of the current chunk.)r r r r r οΏ½getsizeR s z Chunk.getsizec C s&