Changes between Version 38 and Version 39 of SV8Specification

Timestamp:

01/04/08 11:57:12 (16 years ago)

Author:

r2d

Comment:

added Chapter packet

SV8Specification

@@ -47 +47 @@
 || [wiki:SV8Specification#AudioPacket Audio Packet] || AP || yes ||
 || [wiki:SV8Specification#SeekTablePacket Seek Table] || ST || no ||
+|| [wiki:SV8Specification#Chapter-TagPacket Chapter-Tag] || CT || no ||
 || [wiki:SV8Specification#StreamEndPacket Stream End] || SE || yes ||
 
@@ -151 +152 @@
 
 
+== Chapter-Tag Packet ==
+
+This packet key is "CT".[[BR]]
+It contains a chapter position and associated tag.[[BR]]
+There is 1 packet for each chapter.
+When used in a file, all CT packets must be consecutive. They must be the next (group of) packet after Seek Table packet if present, or the last (group of) packet before the Stream End packet else.[[BR]]
+When used while streaming, this packet can be inserted between AP packets, and the tag data is valid for the next samples, until a new CT packet is sent.
+
+|| '''Field''' || '''Size (bits)''' || '''Value''' || '''Comment''' ||
+|| Sample offset || n*8; 0 < n < 10 ||  || Position of the chapter in samples. In a file from the beginning of the file, in a stream from the last sample before this packet ||
+|| Chapter number || n*8; 0 < n < 10 ||  || 0 in the case of streaming, else starts from 1 ||
+|| APEv2 tag || n*8 ||  || [http://wiki.hydrogenaudio.org/index.php?title=APEv2_specification APEv2 tag] without the preamble { 'A', 'P', 'E', 'T', 'A', 'G', 'E', 'X' } in the header or footer, preferably without footer ||
+
+
 == Security Packet ==
 
@@ -160 +175 @@
 
 This packet key is "SE".[[BR]]
-Recommended packet size is 3 bytes.[[BR]]
+The packet size must be 3 bytes.[[BR]]
 This packet is mandatory and must be the last stream packet. Tags, if present, must be written after this packet.
 
@@ -167 +182 @@
 
 This file format can be used for streaming. The "SH" block is (can?) used as synchronization marker. The decoder will scan for a "SH" block and check its CRC. Once the decoder is synchronized, it will start decoding. It's up to the streaming server to choose when to send "SH" block.[[BR]]
-There is currently no way to send tags during playback. This must be changed (a tag packet ?).
+To send meta data while streaming, the Chapter-Tag packet can be used.
 
 
@@ -173 +188 @@
 
 No packet must be written after the stream end packet to allow tagging by other applications.[[BR]]
-Remarks about tagging? Incompatibilities?[[BR]]
+Those tags are global to the file, and defines the default values for all the tag fields. The Chapter-Tag packet can redefine the field value for each chapter.
 
 == Exemple file ==