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/ IRIX Base Documentation 2002 November / SGI IRIX Base Documentation 2002 November.iso / usr / share / catman / p_man / cat3dm / dmedia / dmMPEG1AudioHeaderGetBlockBytes.z / dmMPEG1AudioHeaderGetBlockBytes
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Text File  |  2002-10-03  |  6.5 KB  |  133 lines
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  4. ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((3333ddddmmmm))))      ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((3333ddddmmmm))))
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  8. NNNNAAAAMMMMEEEE
  9.      dmMPEG1AudioHeaderGetBlockBytes - gets expected length in bytes of any
  10.      compressed data block.
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  13. SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
  14.      ####iiiinnnncccclllluuuuddddeeee <<<<ddddmmmmeeeeddddiiiiaaaa////ddddmmmmeeeeddddiiiiaaaa....hhhh>>>>
  15.      ####iiiinnnncccclllluuuuddddeeee <<<<ddddmmmmeeeeddddiiiiaaaa////ddddmmmm____aaaauuuuddddiiiioooouuuuttttiiiillll....hhhh>>>>
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  17.      DDDDMMMMssssttttaaaattttuuuussss ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((DDDDMMMMMMMMPPPPEEEEGGGG1111aaaauuuuddddiiiiooooddddeeeeccccooooddddeeeerrrr ddddeeeeccccooooddddeeeerrrr,,,,
  18.                                          uuuunnnnssssiiiiggggnnnneeeedddd cccchhhhaaaarrrr ****ccccmmmmppppDDDDaaaattttaaaa,,,,
  19.                                          iiiinnnntttt ****bbbblllloooocccckkkkSSSSiiiizzzzeeee))))
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  22. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRR
  23.      _d_e_c_o_d_e_r   DDDDMMMMMMMMPPPPEEEEGGGG1111aaaauuuuddddiiiiooooddddeeeeccccooooddddeeeerrrr structure, created by
  24.                ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooDDDDeeeeccccooooddddeeeerrrrCCCCrrrreeeeaaaatttteeee((((3333ddddmmmm)))), specifies and stores the signal
  25.                processing parameters.  It describes the kind of decompression
  26.                to perform, and holds the between-block state of the
  27.                decompressor.  It is initially generated by calls to
  28.                ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooDDDDeeeeccccooooddddeeeerrrrCCCCrrrreeeeaaaatttteeee((((3333ddddmmmm)))) and
  29.                ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooDDDDeeeeccccooooddddeeeerrrrSSSSeeeettttPPPPaaaarrrraaaammmmssss((((3333ddddmmmm)))).
  30.                ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss modifies DDDDMMMMMMMMPPPPEEEEGGGG1111aaaauuuuddddiiiiooooddddeeeeccccooooddddeeeerrrr
  31.                structure to reflect the header on the compressed data block if
  32.                one is found; decoder parameters may then subsequenly be
  33.                queried using ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooDDDDeeeeccccooooddddeeeerrrrSSSSeeeettttPPPPaaaarrrraaaammmmssss((((3333ddddmmmm)))) to determine
  34.                the decoding parameters of the encoded bytes.
  35.  
  36.  
  37.      _c_m_p_D_a_t_a   points to a block of data bytes presumed to constitute the
  38.                compressed data stream.
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  41.      _b_l_o_c_k_S_i_z_e pointer to an integer return value; indicates the expected
  42.                length in bytes of any compressed data block starting from the
  43.                header that was found. If no valid header was found zero is
  44.                returned.  This may be useful number of bytes to queue up for
  45.                calls to ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooDDDDeeeeccccooooddddeeee((((3333ddddmmmm)))).  The largest compressed data
  46.                block possible under MPEG1 audio layer 1 is 672 bytes (32kHz
  47.                sampling rate, 448 kbps data rate, 38 sample frames per block)
  48.                and under layer 2 it is 1728 bytes (32kHz sampling rate, 384
  49.                kbps data rate, 1152 sample frames per block) -- ???.
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  52. RRRREEEETTTTUUUURRRRNNNNEEEEDDDD VVVVAAAALLLLUUUUEEEE
  53.      Returns DDDDMMMM____FFFFAAAAIIIILLLLUUUURRRREEEE or DDDDMMMM____SSSSUUUUCCCCCCCCEEEESSSSSSSS.
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  56. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  57.      ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((3333ddddmmmm)))) extracts information from a
  58.      compressed data stream without going so far as to decompress the data.
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((3333ddddmmmm))))      ddddmmmmMMMMPPPPEEEEGGGG1111AAAAuuuuddddiiiiooooHHHHeeeeaaaaddddeeeerrrrGGGGeeeettttBBBBlllloooocccckkkkBBBByyyytttteeeessss((((3333ddddmmmm))))
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  74. NNNNOOOOTTTTEEEE
  75. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  76.      dmMPEG1AudioDecoderCreate(3dm), dmMPEG1AudioDecoderSetParams(3dm),
  77.      dmMPEG1AudioDecoderGetParams(3dm), dmMPEG1AudioDecode(3dm).
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  129.                                                                         PPPPaaaaggggeeee 2222
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