1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
exception No_dirac
open Schroedinger
let infile = ref "input.ogg"
let outfile = ref "output.ogg"
let debug = ref false
let quality = ref 35.
let () =
Arg.parse
[
"-d", Arg.Set debug, "Show debugging messages";
"-o", Arg.Set_string outfile, "Output file";
"-q", Arg.Set_float quality, "Quality of the compression";
"-i", Arg.Set_string infile, "Input file";
]
ignore
"schrotranscode [options]"
let in_init () =
let sync,fd = Ogg.Sync.create_from_file !infile in
let rec fill os =
let page = Ogg.Sync.read sync in
try
(* We drop pages which are not for us.. *)
if Ogg.Page.serialno page =
Ogg.Stream.serialno os
then
Ogg.Stream.put_page os page ;
with
| Ogg.Bad_data -> fill os (* Do not care about page that are not for us.. *)
in
(** Test wether the stream is dirac *)
let test_dirac () =
(** Get First page *)
let page = Ogg.Sync.read sync in
(** Check wether this is a b_o_s *)
if not (Ogg.Page.bos page) then raise No_dirac ;
(** Create a stream with this ID *)
let serial = Ogg.Page.serialno page in
Printf.printf "Testing stream %nx\n" serial ;
let os = Ogg.Stream.create ~serial () in
Ogg.Stream.put_page os page ;
let packet = Ogg.Stream.get_packet os in
(** Test header. Do not catch anything, first page should be sufficient *)
if not (Decoder.check packet) then
raise Not_found;
Printf.printf "Got a dirac stream !\n" ;
(** Get second packet *)
let rec f () =
try
Ogg.Stream.get_packet os
with
| Ogg.Not_enough_data -> (fill os; f ())
in
let packet2 = f () in
let dec = Decoder.create packet packet2 in
let video_format = Decoder.get_video_format dec in
serial,os,dec,video_format
in
(** Now find a theora stream *)
let rec init () =
try
test_dirac ()
with
| Not_found ->
( Printf.printf "This stream was not dirac..\n";
init () )
| No_dirac ->
( Printf.printf "No dirac stream was found..\n%!";
raise No_dirac )
in
let serial,os,t,video_format = init () in
Printf.printf
"Ogg logical stream %nx is Dirac %dx%d %.02f fps video\n"
serial video_format.width video_format.height
((float_of_int video_format.frame_rate_numerator) /.
(float_of_int video_format.frame_rate_denominator)) ;
flush_all ();
t,os,fill,video_format,fd
let out_init video_format =
let oc = open_out !outfile in
let out s = output_string oc s; flush oc in
let os = Ogg.Stream.create () in
let enc = Encoder.create video_format in
Encoder.set_settings enc
{ (Encoder.get_settings enc) with
Schroedinger.Encoder.
rate_control = Encoder.Constant_noise_threshold;
noise_threshold = !quality;
};
out (Ogg.Stream.flush os);
enc,os,out
let () =
let dec,is,fill,video_format,fd = in_init () in
let enc,os,out = out_init video_format in
let latest_frame = ref None in
let rec get_frame () =
try
let frame = Decoder.decode_frame dec is in
latest_frame := Some frame;
frame
with
| Decoder.Skipped_frame ->
begin
match !latest_frame with
| Some f -> f
| None -> assert false
end
| Ogg.Not_enough_data when not (Ogg.Stream.eos is) ->
(fill is; get_frame ())
in
let rec generator () =
try
Encoder.encode_frame enc (get_frame ()) os;
Ogg.Stream.get_page os
with
| Ogg.Not_enough_data when not (Ogg.Stream.eos is) ->
generator ()
in
Printf.printf "Starting transcoding loop !\n%!";
begin
try
while true do
let op = generator () in
let s_o_p (h,b) = h ^ b in
let op = s_o_p op in
out op;
done;
with
| Ogg.Not_enough_data -> ()
end ;
Encoder.eos enc os;
out (Ogg.Stream.flush os);
Unix.close fd;
Printf.printf "Transcoding is finished..\n"
let () = Gc.full_major ()
|
