/*
  * MPEG4 encoder/decoder internal header.
  * Copyright (c) 2000,2001 Fabrice Bellard
  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
  *
  * 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_MPEG4VIDEO_H
 #define AVCODEC_MPEG4VIDEO_H
 

 #include <stdint.h>

 #include "get_bits.h"
 #include "mpegvideo.h"
 #include "rl.h"
 

 // shapes
 #define RECT_SHAPE       0
 #define BIN_SHAPE        1
 #define BIN_ONLY_SHAPE   2
 #define GRAY_SHAPE       3
 

 #define SIMPLE_VO_TYPE           1
 #define CORE_VO_TYPE             3
 #define MAIN_VO_TYPE             4
 #define NBIT_VO_TYPE             5
 #define ARTS_VO_TYPE            10
 #define ACE_VO_TYPE             12
 #define ADV_SIMPLE_VO_TYPE      17

 
 // aspect_ratio_info
 #define EXTENDED_PAR 15
 
 //vol_sprite_usage / sprite_enable
 #define STATIC_SPRITE 1
 #define GMC_SPRITE 2
 
 #define MOTION_MARKER 0x1F001
 #define DC_MARKER     0x6B001
 
 #define VOS_STARTCODE        0x1B0
 #define USER_DATA_STARTCODE  0x1B2
 #define GOP_STARTCODE        0x1B3
 #define VISUAL_OBJ_STARTCODE 0x1B5
 #define VOP_STARTCODE        0x1B6
 

 /* smaller packets likely don't contain a real frame */
 #define MAX_NVOP_SIZE 19
 

 typedef struct Mpeg4DecContext {
     MpegEncContext m;

     /// number of bits to represent the fractional part of time

     int time_increment_bits;

     int shape;

     int vol_sprite_usage;

     int sprite_brightness_change;

     int num_sprite_warping_points;

     /// sprite trajectory points

     uint16_t sprite_traj[4][2];

     /// sprite shift [isChroma]

     int sprite_shift[2];

     // reversible vlc
     int rvlc;

     /// could this stream contain resync markers

     int resync_marker;

     /// time distance of first I -> B, used for interlaced B-frames

     int t_frame;

     int new_pred;

     int enhancement_type;

     int scalability;

     int use_intra_dc_vlc;

     /// QP above which the ac VLC should be used for intra dc

     int intra_dc_threshold;

     /* bug workarounds */
     int divx_version;
     int divx_build;
     int xvid_build;
     int lavc_build;

     /// flag for having shown the warning about invalid Divx B-frames

     int showed_packed_warning;

     /** does the stream contain the low_delay flag,
      *  used to work around buggy encoders. */
     int vol_control_parameters;

     int cplx_estimation_trash_i;
     int cplx_estimation_trash_p;
     int cplx_estimation_trash_b;

 } Mpeg4DecContext;
 

 /* dc encoding for mpeg4 */

 extern const uint8_t ff_mpeg4_DCtab_lum[13][2];
 extern const uint8_t ff_mpeg4_DCtab_chrom[13][2];

 extern const uint16_t ff_mpeg4_intra_vlc[103][2];

 extern const int8_t ff_mpeg4_intra_level[102];
 extern const int8_t ff_mpeg4_intra_run[102];
 

 extern RLTable ff_mpeg4_rl_intra;

 
 /* Note this is identical to the intra rvlc except that it is reordered. */

 extern RLTable ff_rvlc_rl_inter;
 extern RLTable ff_rvlc_rl_intra;

 extern const uint16_t ff_sprite_trajectory_tab[15][2];
 extern const uint8_t ff_mb_type_b_tab[4][2];

 
 /* these matrixes will be permuted for the idct */
 extern const int16_t ff_mpeg4_default_intra_matrix[64];
 extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
 
 extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
 extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
 extern const uint16_t ff_mpeg4_resync_prefix[8];
 

 extern const uint8_t ff_mpeg4_dc_threshold[8];

 void ff_mpeg4_encode_mb(MpegEncContext *s,

                         int16_t block[6][64],

                         int motion_x, int motion_y);

 void ff_mpeg4_pred_ac(MpegEncContext *s, int16_t *block, int n,

                       int dir);

 void ff_set_mpeg4_time(MpegEncContext *s);

 void ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);

 int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb);

 void ff_mpeg4_encode_video_packet_header(MpegEncContext *s);
 void ff_mpeg4_clean_buffers(MpegEncContext *s);

 void ff_mpeg4_stuffing(PutBitContext *pbc);

 void ff_mpeg4_init_partitions(MpegEncContext *s);
 void ff_mpeg4_merge_partitions(MpegEncContext *s);
 void ff_clean_mpeg4_qscales(MpegEncContext *s);

 int ff_mpeg4_decode_partitions(Mpeg4DecContext *ctx);

 int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s);

 int ff_mpeg4_decode_video_packet_header(Mpeg4DecContext *ctx);

 void ff_mpeg4_init_direct_mv(MpegEncContext *s);

 void ff_mpeg4videodec_static_init(void);

 int ff_mpeg4_workaround_bugs(AVCodecContext *avctx);

 int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size);

 
 /**
  *
  * @return the mb_type
  */
 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my);

 extern uint8_t ff_mpeg4_static_rl_table_store[3][2][2 * MAX_RUN + MAX_LEVEL + 3];

 
 #if 0 //3IV1 is quite rare and it slows things down a tiny bit
 #define IS_3IV1 s->codec_tag == AV_RL32("3IV1")
 #else
 #define IS_3IV1 0
 #endif
 
 /**

  * Predict the dc.

  * encoding quantized level -> quantized diff
  * decoding quantized diff -> quantized level
  * @param n block index (0-3 are luma, 4-5 are chroma)
  * @param dir_ptr pointer to an integer where the prediction direction will be stored
  */

 static inline int ff_mpeg4_pred_dc(MpegEncContext *s, int n, int level,
                                    int *dir_ptr, int encoding)

 {
     int a, b, c, wrap, pred, scale, ret;
     int16_t *dc_val;
 
     /* find prediction */

     if (n < 4)

         scale = s->y_dc_scale;

     else

         scale = s->c_dc_scale;

     if (IS_3IV1)
         scale = 8;

     wrap   = s->block_wrap[n];

     dc_val = s->dc_val[0] + s->block_index[n];
 
     /* B C
      * A X
      */

     a = dc_val[-1];
     b = dc_val[-1 - wrap];
     c = dc_val[-wrap];
 
     /* outside slice handling (we can't do that by memset as we need the
      * dc for error resilience) */
     if (s->first_slice_line && n != 3) {
         if (n != 2)
             b = c = 1024;
         if (n != 1 && s->mb_x == s->resync_mb_x)
             b = a = 1024;

     }

     if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1) {
         if (n == 0 || n == 4 || n == 5)
             b = 1024;

     }
 
     if (abs(a - b) < abs(b - c)) {

         pred     = c;

         *dir_ptr = 1; /* top */
     } else {

         pred     = a;

         *dir_ptr = 0; /* left */
     }
     /* we assume pred is positive */
     pred = FASTDIV((pred + (scale >> 1)), scale);
 

     if (encoding) {

         ret = level - pred;

     } else {

         level += pred;

         ret    = level;

     }
     level *= scale;
     if (level & (~2047)) {
         if (!s->encoding && (s->avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE))) {

             if (level < 0) {
                 av_log(s->avctx, AV_LOG_ERROR,
                        "dc<0 at %dx%d\n", s->mb_x, s->mb_y);

                 return -1;
             }

             if (level > 2048 + scale) {

                 av_log(s->avctx, AV_LOG_ERROR,
                        "dc overflow at %dx%d\n", s->mb_x, s->mb_y);

                 return -1;
             }
         }

         if (level < 0)
             level = 0;
         else if (!(s->workaround_bugs & FF_BUG_DC_CLIP))
             level = 2047;

     }

     dc_val[0] = level;

 
     return ret;
 }

 #endif /* AVCODEC_MPEG4VIDEO_H */