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open Mm_base
open Mm_audio
module YUV420 = Mm_image.Image.YUV420
(** Images from which are made videos. *)
module type Image = sig
type t
val create : int -> int -> t
val size : t -> int
val blit_all : t -> t -> unit
val copy : t -> t
val blank : t -> unit
val randomize : t -> unit
end
module Image = struct
include Mm_image.Image.YUV420
let create w h = create w h
let scale = scale ~proportional:false
end
module Make (Image : Image) = struct
module I = Image
type t = Image.t array
type buffer = t
let make len width height =
Array.init len (fun _ -> Image.create width height)
let single img = [| img |]
let blit sbuf sofs dbuf dofs len =
for i = 0 to len - 1 do
Image.blit_all sbuf.(sofs + i) dbuf.(dofs + i)
done
let copy vid = Array.map Image.copy vid
let length vid = Array.length vid
let size vid =
let n = ref 0 in
for i = 0 to Array.length vid - 1 do
n := !n + Image.size vid.(i)
done;
!n
let get vid i = vid.(i)
let set vid i img = vid.(i) <- img
let iter f vid off len =
for i = off to off + len - 1 do
f vid.(i)
done
let blank vid off len = iter Image.blank vid off len
let randomize vid off len = iter Image.randomize vid off len
end
include Make (Image)
module Canvas = struct
module Image = Mm_image.Image.Canvas (Image)
type image = Image.t
type t = Image.t array
let make len (width, height) : t =
Array.init len (fun _ -> Image.create width height)
let single img = [| img |]
let single_image img = single (Image.make img)
let length (v : t) = Array.length v
let copy (v : t) = Array.init (length v) (fun i -> v.(i))
let size (v : t) =
let n = ref 0 in
for i = 0 to Array.length v - 1 do
n := !n + Image.size v.(i)
done;
!n
let get v i = v.(i)
let set v i img = v.(i) <- img
let map_image f v i = v.(i) <- f v.(i)
let render v i = Image.render v.(i)
let put v i img = v.(i) <- Image.make img
let blit sbuf sofs dbuf dofs len =
for i = 0 to len - 1 do
dbuf.(dofs + i) <- sbuf.(sofs + i)
done
let map f buf ofs len =
for i = ofs to ofs + len - 1 do
buf.(i) <- f buf.(i)
done
let blank buf ofs len =
map
(fun img -> Image.create (Image.width img) (Image.height img))
buf ofs len
let iter f buf ofs len =
for i = ofs to ofs + len - 1 do
buf.(i) <- Image.iter f buf.(i)
done
end
module FPS = struct
type t = float
let to_frac f =
let n = floor ((f *. 100.) +. 0.5) in
let n = int_of_float n in
if n mod 100 = 0 then (n / 100, 1) else (n, 100)
end
module AVI = struct
module Writer = struct
let word n =
let s = Bytes.create 2 in
Bytes.set_int16_le s 0 n;
Bytes.unsafe_to_string s
let dword n =
let s = Bytes.create 4 in
Bytes.set_int32_le s 0 (Int32.of_int n);
Bytes.unsafe_to_string s
module Chunk = struct
let create id len =
let pad = len mod 2 = 1 in
assert (String.length id = 4);
let s = Bytes.create (8 + len + if pad then 1 else 0) in
Bytes.blit_string id 0 s 0 4;
Bytes.blit_string (dword len) 0 s 4 4;
if pad then Bytes.set s (8 + len) (char_of_int 0);
s
let make id data =
let len = String.length data in
let s = create id len in
Bytes.blit_string data 0 s 8 len;
Bytes.unsafe_to_string s
let audio_s16le buf =
let len = Audio.length buf in
let channels = Audio.channels buf in
let s = create "01wb" (len * channels * 2) in
Audio.S16LE.of_audio buf 0 s 8 len;
Bytes.unsafe_to_string s
let video_yuv420 img =
let open Mm_image in
let width = Image.YUV420.width img in
let height = Image.YUV420.height img in
let y, u, v = Image.YUV420.data img in
let y = Image.Data.to_string y in
let u = Image.Data.to_string u in
let v = Image.Data.to_string v in
let y_stride = Image.YUV420.y_stride img in
let uv_stride = Image.YUV420.uv_stride img in
let s = create "00db" (width * height + 2 * (width / 2) * (height / 2)) in
let o = ref 8 in
let add_sub data off len =
Bytes.blit_string data off s !o len;
o := !o + len
in
let add data = add_sub data 0 (String.length data) in
if y_stride = width then add y
else
for j = 0 to height - 1 do
add_sub y (j * y_stride) width
done;
if uv_stride = width / 2 then (
add u;
add v)
else (
for j = 0 to (height / 2) - 1 do
add_sub u (j * uv_stride) (width / 2)
done;
for j = 0 to (height / 2) - 1 do
add_sub v (j * uv_stride) (width / 2)
done);
Bytes.unsafe_to_string s
let list = make "LIST"
end
let ?(format=`YUV420) ~width ~height ~framerate ?channels ?samplerate ?vendor () =
ignore format;
let has_audio = channels <> None in
let channels = Option.value ~default:0 channels in
let samplerate = Option.value ~default:0 samplerate in
assert (not has_audio || samplerate > 0);
let dword_max () = word 0xffff ^ word 0xffff in
let =
Chunk.make "avih"
(dword (1000000 / framerate)
^ dword 0
^ dword 0
^ dword 0x0100
^ dword_max ()
^ dword 0
^ dword (1 + if has_audio then 1 else 0)
^ dword 0
^ dword width
^ dword height
^ dword 0
^ dword 0
^ dword 0
^ dword 0
)
in
let =
let =
Chunk.make "strh"
("vids"
^ "I420"
^ dword 0
^ word 0
^ word 0
^ dword 0
^ dword 1
^ dword framerate
^ dword 0
^ dword_max ()
^ dword 0
^ dword_max ()
^ dword 0
^ word 0
^ word 0
^ word width
^ word height
)
in
let stream_format =
Chunk.make "strf"
(dword 40
^ dword width
^ dword height
^ word 1
^ word 12
^ "I420"
^ dword (width * height * 6 / 4)
^ dword 0
^ dword 0
^ dword 0
^ dword 0
)
in
Chunk.list ("strl" ^ stream_header ^ stream_format)
in
let =
if not has_audio then "" else
let =
Chunk.make "strh"
("auds"
^ dword 0
^ dword 0
^ word 0
^ word 0
^ dword 0
^ dword 1
^ dword samplerate
^ dword 0
^ dword_max ()
^ dword 0
^ dword_max ()
^ dword (2 * channels)
^ word 0
^ word 0
^ word 0
^ word 0 )
in
let stream_format =
Chunk.make "strf"
(word 1
^ word channels
^ dword samplerate
^ dword (2 * channels * samplerate)
^ word (2 * channels)
^ word 16
^ word 0 )
in
Chunk.list ("strl" ^ stream_header ^ stream_format)
in
let = Chunk.list ("hdrl" ^ avi_header ^ video_header ^ audio_header) in
let info =
match vendor with
| Some vendor ->
let producer = Chunk.make "ISFT" vendor in
Chunk.list ("INFO" ^ producer)
| None -> ""
in
"RIFF"
^ dword_max ()
^ "AVI " ^ headers ^ info ^ "LIST" ^ dword_max () ^ "movi"
end
end
module IO = struct
exception Invalid_file
module Reader = struct
class type t =
object
method width : int
method height : int
method frame_rate : float
method read : buffer -> int -> int -> int
method close : unit
end
end
module Writer = struct
class type t =
object
method write : buffer -> int -> int -> unit
method close : unit
end
class virtual avi frame_rate w h =
let frames_per_chunk = int_of_float (frame_rate +. 0.5) in
let frame_size = w * h * 3 in
object (self)
inherit IO.helper
method virtual private stream_write : string -> int -> int -> int
method virtual private stream_seek : int -> unit
method virtual private stream_close : unit
initializer
self#output "RIFF";
self#output_int 0;
self#output "AVI ";
self#output "LIST";
self#output_int 192;
self#output "hdrl";
self#output "avih";
self#output_int 56;
self#output_int (int_of_float (1000000. /. frame_rate));
self#output_int 0;
self#output_int 0;
self#output_byte 0;
self#output_byte 1;
self#output_byte 0;
self#output_byte 0;
self#output_int 0;
self#output_int 0;
self#output_int 1;
self#output_int 0;
self#output_int w;
self#output_int h;
self#output_int 0;
self#output_int 0;
self#output_int 0;
self#output_int 0;
self#output "LIST";
self#output_int 116;
self#output "strl";
self#output "strh";
self#output_int 56;
self#output "vids";
self#output "RGB ";
self#output_int 0;
self#output_int 0;
self#output_int 0;
self#output_int 10;
self#output_int (int_of_float (frame_rate *. 10.));
self#output_int 0;
self#output_int 0;
self#output_int (frames_per_chunk * frame_size);
self#output_int 0;
self#output_int 0;
self#output_short 0;
self#output_short 0;
self#output_short w;
self#output_short h;
self#output "strf";
self#output_int 40;
self#output_int 40;
self#output_int w;
self#output_int h;
self#output_short 1;
self#output_short 24;
self#output_int 0;
self#output_int frame_size;
self#output_int 0;
self#output_int 0;
self#output_int 0;
self#output_int 0;
self#output "LIST";
self#output_int 0;
self#output "movi";
self#output "00dc";
self#output_int 0
val mutable datalen = 0
val mutable dataframes = 0
method write (_ : buffer) ofs len =
for _ = ofs to ofs + len - 1 do
let s = failwith "TODO: output YUV420 avi" in
self#output s;
datalen <- datalen + String.length s
done;
dataframes <- dataframes + len
method close =
Printf.printf "completing... (%d frames)\n%!" dataframes;
self#stream_seek 4;
self#output_int (datalen + (56 * 4));
self#stream_seek (12 * 4);
self#output_int dataframes;
self#stream_seek (35 * 4);
self#output_int dataframes;
self#stream_seek (54 * 4);
self#output_int (datalen + (3 * 4));
self#stream_seek (57 * 4);
self#output_int datalen;
self#stream_close
end
class to_avi_file fname fr w h =
object
inherit avi fr w h
inherit IO.Unix.rw ~write:true fname
end
end
end