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(*
* Copyright 2003-2011 Savonet team
*
* This file is part of ocaml-opus.
*
* ocaml-opus is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* ocaml-opus is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with ocaml-opus; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*)
let check = Opus.Decoder.check_packet
let buflen = Opus.recommended_frame_size
let decoder_samplerate = ref 48000
let decoder ~fill:_ os =
let decoder = ref None in
let packet1 = ref None in
let packet2 = ref None in
let os = ref os in
let init () =
match !decoder with
| None ->
let packet1 =
match !packet1 with
| None ->
let p = Ogg.Stream.get_packet !os in
packet1 := Some p;
p
| Some p -> p
in
let packet2 =
match !packet2 with
| None ->
let p = Ogg.Stream.get_packet !os in
packet2 := Some p;
p
| Some p -> p
in
let dec =
Opus.Decoder.create ~samplerate:!decoder_samplerate packet1 packet2
in
let chans = Opus.Decoder.channels dec in
let meta = Opus.Decoder.comments dec in
decoder := Some (dec, chans, meta);
(dec, chans, meta)
| Some dec -> dec
in
let info () =
let _, chans, meta = init () in
({ Ogg_decoder.channels = chans; sample_rate = !decoder_samplerate }, meta)
in
let restart ~fill:_ new_os =
os := new_os;
decoder := None;
ignore (init ())
in
let decode ~decode_float ~make_float ~sub_float feed =
let dec, chans, _ = init () in
let chan _ = make_float buflen in
let buf = Array.init chans chan in
let ret = decode_float dec !os buf 0 buflen in
feed (Array.map (fun x -> sub_float x 0 ret) buf)
in
let decoder ~decode_float ~make_float ~sub_float =
{
Ogg_decoder.name = "opus";
info;
decode = decode ~decode_float ~make_float ~sub_float;
restart;
samples_of_granulepos = (fun x -> x);
}
in
Ogg_decoder.Audio_both
( decoder ~decode_float:Opus.Decoder.decode_float
~make_float:(fun len -> Array.make len 0.)
~sub_float:Array.sub,
decoder ~decode_float:Opus.Decoder.decode_float_ba
~make_float:(Bigarray.Array1.create Bigarray.float32 Bigarray.c_layout)
~sub_float:Bigarray.Array1.sub )
let register () = Hashtbl.add Ogg_decoder.ogg_decoders "opus" (check, decoder)
|
