/*
  * 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
  */
 
 #ifndef AVCODEC_AVDCT_H
 #define AVCODEC_AVDCT_H
 
 #include "libavutil/opt.h"
 
 /**
  * AVDCT context.
  * @note function pointers can be NULL if the specific features have been
  *       disabled at build time.
  */
 typedef struct AVDCT {
     const AVClass *av_class;
 
     void (*idct)(int16_t *block /* align 16 */);
 
     /**
      * IDCT input permutation.
      * Several optimized IDCTs need a permutated input (relative to the
      * normal order of the reference IDCT).
      * This permutation must be performed before the idct_put/add.
      * Note, normally this can be merged with the zigzag/alternate scan<br>
      * An example to avoid confusion:
      * - (->decode coeffs -> zigzag reorder -> dequant -> reference IDCT -> ...)
      * - (x -> reference DCT -> reference IDCT -> x)
      * - (x -> reference DCT -> simple_mmx_perm = idct_permutation
      *    -> simple_idct_mmx -> x)
      * - (-> decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant
      *    -> simple_idct_mmx -> ...)
      */
     uint8_t idct_permutation[64];
 
     void (*fdct)(int16_t *block /* align 16 */);
 
 
     /**
      * DCT algorithm.
      * must use AVOptions to set this field.
      */
     int dct_algo;
 
     /**
      * IDCT algorithm.
      * must use AVOptions to set this field.
      */
     int idct_algo;

 
     void (*get_pixels)(int16_t *block /* align 16 */,
                        const uint8_t *pixels /* align 8 */,

                        ptrdiff_t line_size);

 
     int bits_per_sample;

 } AVDCT;
 
 /**
  * Allocates a AVDCT context.
  * This needs to be initialized with avcodec_dct_init() after optionally
  * configuring it with AVOptions.
  *
  * To free it use av_free()
  */
 AVDCT *avcodec_dct_alloc(void);
 int avcodec_dct_init(AVDCT *);
 

 const AVClass *avcodec_dct_get_class(void);
 

 #endif /* AVCODEC_AVDCT_H */