Changes between Version 47 and Version 48 of SV8Specification


Ignore:
Timestamp:
02/24/09 05:15:52 (16 years ago)
Author:
shy
Comment:

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Legend:

Unmodified
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  • SV8Specification

    v47 v48  
    6767[[Image(final.png, nolink)]] [[BR]]
    6868This packet key is "SH".[[BR]]
    69 It contains the informations needed to decode the stream. This block is mandatory and must be written before the first audio packet.[[BR]]
     69It contains the information needed to decode the stream. This block is mandatory and must be written before the first audio packet.[[BR]]
    7070
    7171|| '''Field''' || '''Size (bits)''' || '''Value''' || '''Comment''' ||
    … …  
    8080|| Audio block frames || 3 || 0..7 || Number of frames per audio packet (4^value^=(1..16384)) ||
    8181
    82 Do we need to specify the channel position ? Is there standard positions / order of the channels ?
    83 
    84 The SV8 stream allows to start decoding only on first packet frame, so cutting the stream requires cutting on packet boundaries. Beginning silence and sample count fields provide more precise cutting possibilities.[[BR]]
     82Do we need to specify the channel position ? There seems to be no standard for positions / order of the channels .
     83
     84The SV8 stream allows to start decoding only on the first packet frame, so cutting the stream requires cutting on packet boundaries. Beginning silence and sample count fields provide more precise cutting possibilities.[[BR]]
    8585
    8686Frequency table
    … …  
    109109The 0 value means that this field has not been computed (no gain must be applied in this case.[[BR]]
    110110exemples :[[BR]]
    111  * Replay gain finds that this title has a loudness of 78.56 dB, it will be encoded as 78.56 * 256 ~ 20111 = 0x4E8F
    112  * For 16 bits output (range [-32767 32768]), the max is 68813 (out of range). it will be encoded as 20 * log10(68813) * 256 ~ 24769 = 0x60C1
    113  * For float output (range [-1 1]), the max is 0.96. it will be encoded as 20 * log10(0.96 * 2^15^) * 256 ~ 23029 = 0x59F5 (for peak values it is suggested to round to nearest higher integer)
     111 * Replay gain finds that this title has a loudness of 78.56 dB. It will be encoded as 78.56 * 256 ~ 20111 = 0x4E8F
     112 * For 16-bit output (range [-32767 32768]), the max is 68813 (out of range). It will be encoded as 20 * log10(68813) * 256 ~ 24769 = 0x60C1
     113 * For float output (range [-1 1]), the max is 0.96. It will be encoded as 20 * log10(0.96 * 2^15^) * 256 ~ 23029 = 0x59F5 (for peak values it is suggested to round to nearest higher integer)
    114114
    115115== Encoder Info Packet ==
    … …  
    211211
    212212[[Image(final.png, nolink)]] [[BR]]
    213 No packet must be written after the stream end packet to allow tagging by other applications.[[BR]]
     213No packet must be written after the stream end packet, to allow tagging by other applications.[[BR]]
    214214Those tags are global to the file, and define the default values for all the tag fields. The Chapter-Tag packet can redefine the field value for each chapter.
    215215
    216216== Exemple file ==
    217217
    218 Packets keys and magick number are highlighted :
     218Packets keys and magic number are highlighted :
    219219
    220220{{{