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open Avutil
module AudioConverter = Swresample.Make (Swresample.Frame) (Swresample.S32Bytes)
module VideoConverter = Swscale.Make (Swscale.Frame) (Swscale.BigArray)
(* module VideoConverter = Swscale.Make (Swscale.Frame) (Swscale.Frame) *)
let () =
if Array.length Sys.argv < 4 then (
Printf.eprintf
" usage: %s input_file video_output_file audio_output_file\n\
\ API example program to show how to read frames from an input file. \n\
\ This program reads frames from a file, decodes them, and writes \
decoded\n\
\ video frames to a rawvideo file named video_output_file, and \
decoded\n\
\ audio frames to a rawaudio file named audio_output_file.\n"
Sys.argv.(0);
exit 1);
Avutil.Log.set_level `Debug;
Avutil.Log.set_callback print_string;
let input_filename = Sys.argv.(1) in
let video_output_filename = Sys.argv.(2) in
let audio_output_filename = Sys.argv.(3) in
let src = Av.open_input input_filename in
Av.get_input_metadata src
|> List.iter (fun (k, v) -> print_endline (k ^ " : " ^ v));
let audio_index, audio_stream, audio_codec = Av.find_best_audio_stream src in
let a_ctx =
AudioConverter.from_codec audio_codec Avutil.Channel_layout.stereo 44100
in
let audio_output_file = open_out_bin audio_output_filename in
let video_index, video_stream, _ = Av.find_best_video_stream src in
(* let v_ctx = VideoConverter.from_codec video_codec 800 600 `Yuv420p in *)
let v_ctx = VideoConverter.create [] 352 288 `Yuv420p 800 600 `Yuv420p in
let video_output_file = open_out_bin video_output_filename in
let rec decode () =
match
Av.read_input ~audio_frame:[audio_stream] ~video_frame:[video_stream] src
with
| `Audio_frame (idx, af) ->
if idx = audio_index then
AudioConverter.convert a_ctx af |> output_bytes audio_output_file;
decode ()
| `Video_frame (idx, vf) ->
if idx = video_index then VideoConverter.convert v_ctx vf |> ignore
(*output_video video_output_file*);
decode ()
| `Subtitle_frame (_, sf) ->
let _, _, lines = Subtitle.frame_to_lines sf in
lines |> List.iter print_endline;
decode ()
| exception Error `Eof -> ()
| exception Error err -> prerr_endline (Avutil.string_of_error err)
| _ -> assert false
in
decode ();
Av.close src;
close_out video_output_file;
close_out audio_output_file;
Printf.printf "Demuxing succeeded.\n";
Printf.printf
"Play the output audio file with the command:\n\
ffplay -f %s -ac 2 -ar 44100 %s\n"
(Option.get (Sample_format.get_name `S32)
^ if Sys.big_endian then "be" else "le")
audio_output_filename;
Gc.full_major ();
Gc.full_major ()
|
