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|
open Avutil
let () = Printexc.record_backtrace true
let fill_yuv_image width height frame_index planes =
(* Y *)
let data_y, linesize_y = planes.(0) in
for y = 0 to height - 1 do
let off = y * linesize_y in
for x = 0 to width - 1 do
data_y.{x + off} <- x + y + (frame_index * 3)
done
done;
(* Cb and Cr *)
let data_cb, linesize_cb = planes.(1) in
let data_cr, _ = planes.(2) in
for y = 0 to (height / 2) - 1 do
let off = y * linesize_cb in
for x = 0 to (width / 2) - 1 do
data_cb.{x + off} <- 128 + y + (frame_index * 2);
data_cr.{x + off} <- 64 + x + (frame_index * 5)
done
done
let () =
if Array.length Sys.argv < 4 then (
Printf.eprintf "Usage: %s <output file> <pixel format> <codec name>\n"
Sys.argv.(0);
exit 1);
Avutil.Log.set_level `Debug;
Avutil.Log.set_callback print_string;
let width = 352 in
let height = 288 in
let pixel_format = Avutil.Pixel_format.of_string Sys.argv.(2) in
let () =
let string_of_flag = function
| `Be -> "be"
| `Pal -> "pal"
| `Bitstream -> "bitstream"
| `Hwaccel -> "hwaccel"
| `Planar -> "planar"
| `Rgb -> "rgb"
| `Pseudopal -> "pseudopal"
| `Alpha -> "alpha"
| `Bayer -> "bayer"
| `Float -> "float"
| `Xyz -> "xyz"
in
let string_of_comp { Avutil.Pixel_format.plane; step; shift; offset; depth }
=
Printf.sprintf "plane: %i, step: %i, shift: %i, offset: %i, depth: %i"
plane step shift offset depth
in
let descriptor = Avutil.Pixel_format.descriptor pixel_format in
Printf.printf
"Pixel format:\n\
name: %s\n\
nb_components: %i\n\
log2_chroma_w: %i\n\
log2_chroma_h: %i\n\
flags: %s\n\
comp: [\n\
\ %s\n\
]\n\
alias: %s\n\
bits: %i\n"
descriptor.Avutil.Pixel_format.name
descriptor.Avutil.Pixel_format.nb_components
descriptor.Avutil.Pixel_format.log2_chroma_w
descriptor.Avutil.Pixel_format.log2_chroma_h
(String.concat ", "
(List.map string_of_flag descriptor.Avutil.Pixel_format.flags))
(String.concat ",\n "
(List.map string_of_comp descriptor.Avutil.Pixel_format.comp))
(match descriptor.Avutil.Pixel_format.alias with
| None -> "N/A"
| Some a -> a)
(Avutil.Pixel_format.bits descriptor)
in
let codec = Avcodec.Video.find_encoder_by_name Sys.argv.(3) in
let dst = Av.open_output Sys.argv.(1) in
let frame_rate = { Avutil.num = 25; den = 1 } in
let time_base = { Avutil.num = 1; den = 25 } in
let pts = ref 0L in
let ovs =
Av.new_video_stream ~width ~height ~frame_rate ~time_base ~pixel_format
~codec dst
in
let frame = Video.create_frame width height pixel_format in
for i = 0 to 240 do
Video.frame_visit ~make_writable:true (fill_yuv_image width height i) frame
|> fun frame ->
Avutil.Frame.set_pts frame (Some !pts);
pts := Int64.succ !pts;
Av.write_frame ovs frame
done;
Av.close dst;
Gc.full_major ();
Gc.full_major ()
|
