(*
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * This is a part of the Pascal port of ffmpeg.
 * - Changes and updates by the UltraStar Deluxe Team
 *
 * Conversion of libavutil/audioconvert.h
 * avutil version 50.43.0
 *
 *)

(**
 * @file
 * audio conversion routines
 *)

const
  {* Audio channel masks *}
  AV_CH_FRONT_LEFT             = $00000001;
  AV_CH_FRONT_RIGHT            = $00000002;
  AV_CH_FRONT_CENTER           = $00000004;
  AV_CH_LOW_FREQUENCY          = $00000008;
  AV_CH_BACK_LEFT              = $00000010;
  AV_CH_BACK_RIGHT             = $00000020;
  AV_CH_FRONT_LEFT_OF_CENTER   = $00000040;
  AV_CH_FRONT_RIGHT_OF_CENTER  = $00000080;
  AV_CH_BACK_CENTER            = $00000100;
  AV_CH_SIDE_LEFT              = $00000200;
  AV_CH_SIDE_RIGHT             = $00000400;
  AV_CH_TOP_CENTER             = $00000800;
  AV_CH_TOP_FRONT_LEFT         = $00001000;
  AV_CH_TOP_FRONT_CENTER       = $00002000;
  AV_CH_TOP_FRONT_RIGHT        = $00004000;
  AV_CH_TOP_BACK_LEFT          = $00008000;
  AV_CH_TOP_BACK_CENTER        = $00010000;
  AV_CH_TOP_BACK_RIGHT         = $00020000;
  AV_CH_STEREO_LEFT            = $20000000;  ///< Stereo downmix.
  AV_CH_STEREO_RIGHT           = $40000000;  ///< See AV_CH_STEREO_LEFT.

(** Channel mask value used for AVCodecContext.request_channel_layout
 *  to indicate that the user requests the channel order of the decoder output
 *  to be the native codec channel order.
 *)
  AV_CH_LAYOUT_NATIVE          = $8000000000000000;

(* Audio channel convenience macros *)
  AV_CH_LAYOUT_MONO            = (AV_CH_FRONT_CENTER);
  AV_CH_LAYOUT_STEREO          = (AV_CH_FRONT_LEFT or AV_CH_FRONT_RIGHT);
  AV_CH_LAYOUT_2_1             = (AV_CH_LAYOUT_STEREO or AV_CH_BACK_CENTER);
  AV_CH_LAYOUT_SURROUND        = (AV_CH_LAYOUT_STEREO or AV_CH_FRONT_CENTER);
  AV_CH_LAYOUT_4POINT0         = (AV_CH_LAYOUT_SURROUND or AV_CH_BACK_CENTER);
  AV_CH_LAYOUT_2_2             = (AV_CH_LAYOUT_STEREO or AV_CH_SIDE_LEFT or AV_CH_SIDE_RIGHT);
  AV_CH_LAYOUT_QUAD            = (AV_CH_LAYOUT_STEREO or AV_CH_BACK_LEFT or AV_CH_BACK_RIGHT);
  AV_CH_LAYOUT_5POINT0         = (AV_CH_LAYOUT_SURROUND or AV_CH_SIDE_LEFT or AV_CH_SIDE_RIGHT);
  AV_CH_LAYOUT_5POINT1         = (AV_CH_LAYOUT_5POINT0 or AV_CH_LOW_FREQUENCY);
  AV_CH_LAYOUT_5POINT0_BACK    = (AV_CH_LAYOUT_SURROUND or AV_CH_BACK_LEFT or 
                                  AV_CH_BACK_RIGHT);
  AV_CH_LAYOUT_5POINT1_BACK    = (AV_CH_LAYOUT_5POINT0_BACK or AV_CH_LOW_FREQUENCY);
  AV_CH_LAYOUT_7POINT0         = (AV_CH_LAYOUT_5POINT0 or AV_CH_BACK_LEFT or AV_CH_BACK_RIGHT);
  AV_CH_LAYOUT_7POINT1         = (AV_CH_LAYOUT_5POINT1 or AV_CH_BACK_LEFT or AV_CH_BACK_RIGHT);
  AV_CH_LAYOUT_7POINT1_WIDE    = (AV_CH_LAYOUT_5POINT1_BACK or 
                                  AV_CH_FRONT_LEFT_OF_CENTER or
                                  AV_CH_FRONT_RIGHT_OF_CENTER);
  AV_CH_LAYOUT_STEREO_DOWNMIX  = (AV_CH_STEREO_LEFT or AV_CH_STEREO_RIGHT);

(**
 * Return a channel layout id that matches name, 0 if no match.
 *)
function av_get_channel_layout(name: {const} PAnsiChar): cint64;
  cdecl; external av__util;

(**
 * Return a description of a channel layout.
 * If nb_channels is <= 0, it is guessed from the channel_layout.
 *
 * @param buf put here the string containing the channel layout
 * @param buf_size size in bytes of the buffer
 *)
procedure av_get_channel_layout_string(buf: PAnsiChar; buf_size: cint; nb_channels: cint; channel_layout: cint64);
  cdecl; external av__util;

(**
 * Return the number of channels in the channel layout.
 *)
function av_get_channel_layout_nb_channels(channel_layout: cint64): cint;
  cdecl; external av__util;