[xiph-commits] r3191 - oogg/trunk

[shans at svn.annodex.net]

Author: shans
Date: 2007-08-14 22:57:29 -0700 (Tue, 14 Aug 2007)
New Revision: 3191

Modified:
   oogg/trunk/granules.ml
   oogg/trunk/granules.mli
   oogg/trunk/packet.ml
Log:
past packet gp reconstruction for Vorbis



Modified: oogg/trunk/granules.ml
===================================================================
--- oogg/trunk/granules.ml	2007-08-14 23:37:24 UTC (rev 3190)
+++ oogg/trunk/granules.ml	2007-08-15 05:57:29 UTC (rev 3191)
@@ -58,5 +58,37 @@
   | Theora -> theora_time bos
   | _      -> fun x -> None
 
-let calculate_next_gp id (Some (a,b,c,d)) = Some (a,b,c,d+1)
-let calculate_last_gp id (Some (a,b,c,d)) = Some (a,b,c,d-1)
+(* there are pretty much always 2 modes, with size bits of 0 and 1 respectively.
+   for now we'll assume that is *always* the case. *)
+let vorbis_last_gp bos prevpack thispack thisgp = 
+  let bos_packet = List.hd bos.raw_data in
+  let long_size = 1 lsl ((extract_int8 bos_packet 28) lsr 4) in
+  let short_size = 1 lsl ((extract_int8 bos_packet 28) land 0xF) in
+  if thisgp = Some (0,0,0,0) then Some (0,0,0,0) else
+  (
+    let len p = if ((extract_int8 p 0) lsr 1) land 1 = 1
+                then long_size else short_size in
+    let thislen = len thispack in
+    let lastlen = len prevpack in
+    match thisgp with
+      | None -> None
+      | Some gp -> 
+                Some (int64_to_oogg64 (Int64.sub (oogg64_to_int64 gp) 
+                    (Int64.of_int ((thislen + lastlen) / 4))))
+  );;
+
+let theora_last_gp = vorbis_last_gp;;
+
+let last_gp_function id bos = match id with
+  | Vorbis -> vorbis_last_gp bos
+  | Theora -> theora_last_gp bos
+  | _      -> fun _ _ _ -> None
+
+let vorbis_next_gp bos prevpack thispack (Some (a,b,c,d)) = (Some (a,b,c,d+1));;
+let theora_next_gp = vorbis_last_gp;;
+
+let next_gp_function id bos = match id with
+  | Vorbis -> vorbis_next_gp bos
+  | Theora -> theora_next_gp bos
+  | _      -> fun _ _ _ -> None
+

Modified: oogg/trunk/granules.mli
===================================================================
--- oogg/trunk/granules.mli	2007-08-14 23:37:24 UTC (rev 3190)
+++ oogg/trunk/granules.mli	2007-08-15 05:57:29 UTC (rev 3191)
@@ -1,7 +1,8 @@
 val granulerate_function : Types.mediaType -> Types.rawPage -> 
                     (Types.granulePos -> float option);;
 
-val calculate_next_gp : Types.mediaType -> Types.granulePos -> 
-                                                            Types.granulePos;;
-val calculate_last_gp : Types.mediaType -> Types.granulePos ->
-                                                            Types.granulePos;;
+val last_gp_function : Types.mediaType -> Types.rawPage ->
+                    string -> string -> Types.granulePos -> Types.granulePos;;
+
+val next_gp_function : Types.mediaType -> Types.rawPage ->
+                    string -> string -> Types.granulePos -> Types.granulePos;;

Modified: oogg/trunk/packet.ml
===================================================================
--- oogg/trunk/packet.ml	2007-08-14 23:37:24 UTC (rev 3190)
+++ oogg/trunk/packet.ml	2007-08-15 05:57:29 UTC (rev 3191)
@@ -37,30 +37,36 @@
 type reconstruct_context = {
   rc_tf : granulePos -> float option;
   mutable rc_cache : packet list;
-  mutable rc_lgp : granulePos
-  (*rc_ngpf : string -> string -> granulePos -> granulePos;*)
+  mutable rc_last_gp : granulePos;
+  mutable rc_last_packet : string;
+  rc_ngpf : string -> string -> granulePos -> granulePos;
+  rc_pgpf : string -> string -> granulePos -> granulePos
 } ;;
 
-(* reconstruct packet given a previous gp *)
+(* reconstruct packet given a previous gp.  Don't store 0 GPs *)
 let packet_from_last_gp crec pack =
-  let gp = crec.rc_lgp in
-  let new_gp = Granules.calculate_next_gp pack.p_page.identity gp in
-  crec.rc_lgp <- new_gp;
+  let gp = crec.rc_last_gp in
+  let new_gp = crec.rc_ngpf crec.rc_last_packet pack.p_data gp in
+  if not (new_gp = Some (0,0,0,0)) 
+  then crec.rc_last_gp <- new_gp;
+  crec.rc_last_packet <- pack.p_data;
   [< '{ pack with p_granulepos = new_gp; p_time = crec.rc_tf new_gp } >]
 
 (* flush the non-timestamped packets from the context record now that we
    have a real granulepos *)
 let new_gp_and_flush crec pack = 
-  let rec _ngaf l gp = match l with
+  let rec _ngaf l p gp = match l with
   | h::t -> (
-    let last_gp = Granules.calculate_last_gp pack.p_page.identity gp in 
-        [< _ngaf t last_gp; 
+    let last_gp = crec.rc_pgpf h.p_data p gp in 
+        [< _ngaf t h.p_data last_gp; 
            '{ h with p_granulepos = last_gp; p_time = crec.rc_tf last_gp } >])
   | [] -> [< >] in
   let l = crec.rc_cache in
   crec.rc_cache <- [];
-  crec.rc_lgp <- pack.p_granulepos;
-  [< _ngaf l pack.p_granulepos; 'pack >]
+  if not (pack.p_granulepos = Some (0,0,0,0)) 
+  then crec.rc_last_gp <- pack.p_granulepos;
+  crec.rc_last_packet <- pack.p_data;
+  [< _ngaf l pack.p_data pack.p_granulepos; 'pack >]
 
 let reconstruct_packet context pack =
   let sn = pack.p_page.raw.serialno in
@@ -74,13 +80,16 @@
       context := 
           (sn, {rc_tf=Granules.granulerate_function id rpage; 
                 rc_cache=[]; 
-                rc_lgp=None})::
+                rc_last_gp=None;
+                rc_last_packet="";
+                rc_pgpf=Granules.last_gp_function id rpage;
+                rc_ngpf=Granules.next_gp_function id rpage})::
                 (!context);
       snd (List.hd !context))
     else List.assoc sn !context
   ) in
   match gp with 
-  | None -> (match crec.rc_lgp with
+  | None -> (match crec.rc_last_gp with
             | None -> (crec.rc_cache <- pack::crec.rc_cache; [< >])
             | Some _ -> packet_from_last_gp crec pack)
   | Some gp -> [< new_gp_and_flush crec pack >];;