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FFmpeg/libavcodec/cavsdec.c

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  1. /*

  2.  * Chinese AVS video (AVS1-P2, JiZhun profile) decoder.

  3.  * Copyright (c) 2006  Stefan Gehrer <stefan.gehrer@gmx.de>

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

  7.  * FFmpeg is free software; you can redistribute it and/or

  8.  * modify it under the terms of the GNU Lesser General Public

  9.  * License as published by the Free Software Foundation; either

  10.  * version 2.1 of the License, or (at your option) any later version.

  11.  *

  12.  * FFmpeg is distributed in the hope that it will be useful,

  13.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  14.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  15.  * Lesser General Public License for more details.

  16.  *

  17.  * You should have received a copy of the GNU Lesser General Public

  18.  * License along with FFmpeg; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. 

  22. /**

  23.  * @file

  24.  * Chinese AVS video (AVS1-P2, JiZhun profile) decoder

  25.  * @author Stefan Gehrer <stefan.gehrer@gmx.de>

  26.  */

  27. 

  28. #include "libavutil/avassert.h"

  29. #include "avcodec.h"

  30. #include "get_bits.h"

  31. #include "golomb.h"

  32. #include "cavs.h"

  33. #include "internal.h"

  34. 

  35. static const uint8_t mv_scan[4] = {

  36.     MV_FWD_X0,MV_FWD_X1,

  37.     MV_FWD_X2,MV_FWD_X3

  38. };

  39. 

  40. static const uint8_t cbp_tab[64][2] = {

  41.   {63, 0},{15,15},{31,63},{47,31},{ 0,16},{14,32},{13,47},{11,13},

  42.   { 7,14},{ 5,11},{10,12},{ 8, 5},{12,10},{61, 7},{ 4,48},{55, 3},

  43.   { 1, 2},{ 2, 8},{59, 4},{ 3, 1},{62,61},{ 9,55},{ 6,59},{29,62},

  44.   {45,29},{51,27},{23,23},{39,19},{27,30},{46,28},{53, 9},{30, 6},

  45.   {43,60},{37,21},{60,44},{16,26},{21,51},{28,35},{19,18},{35,20},

  46.   {42,24},{26,53},{44,17},{32,37},{58,39},{24,45},{20,58},{17,43},

  47.   {18,42},{48,46},{22,36},{33,33},{25,34},{49,40},{40,52},{36,49},

  48.   {34,50},{50,56},{52,25},{54,22},{41,54},{56,57},{38,41},{57,38}

  49. };

  50. 

  51. static const uint8_t scan3x3[4] = { 4, 5, 7, 8 };

  52. 

  53. static const uint8_t cavs_chroma_qp[64] = {

  54.   0,  1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,

  55.   16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,

  56.   32,33,34,35,36,37,38,39,40,41,42,42,43,43,44,44,

  57.   45,45,46,46,47,47,48,48,48,49,49,49,50,50,50,51

  58. };

  59. 

  60. static const uint8_t dequant_shift[64] = {

  61.   14,14,14,14,14,14,14,14,

  62.   13,13,13,13,13,13,13,13,

  63.   13,12,12,12,12,12,12,12,

  64.   11,11,11,11,11,11,11,11,

  65.   11,10,10,10,10,10,10,10,

  66.   10, 9, 9, 9, 9, 9, 9, 9,

  67.   9, 8, 8, 8, 8, 8, 8, 8,

  68.   7, 7, 7, 7, 7, 7, 7, 7

  69. };

  70. 

  71. static const uint16_t dequant_mul[64] = {

  72.   32768,36061,38968,42495,46341,50535,55437,60424,

  73.   32932,35734,38968,42495,46177,50535,55109,59933,

  74.   65535,35734,38968,42577,46341,50617,55027,60097,

  75.   32809,35734,38968,42454,46382,50576,55109,60056,

  76.   65535,35734,38968,42495,46320,50515,55109,60076,

  77.   65535,35744,38968,42495,46341,50535,55099,60087,

  78.   65535,35734,38973,42500,46341,50535,55109,60097,

  79.   32771,35734,38965,42497,46341,50535,55109,60099

  80. };

  81. 

  82. #define EOB 0,0,0

  83. 

  84. static const struct dec_2dvlc intra_dec[7] = {

  85.   {

  86.     { //level / run / table_inc

  87.       {  1, 1, 1},{ -1, 1, 1},{  1, 2, 1},{ -1, 2, 1},{  1, 3, 1},{ -1, 3, 1},

  88.       {  1, 4, 1},{ -1, 4, 1},{  1, 5, 1},{ -1, 5, 1},{  1, 6, 1},{ -1, 6, 1},

  89.       {  1, 7, 1},{ -1, 7, 1},{  1, 8, 1},{ -1, 8, 1},{  1, 9, 1},{ -1, 9, 1},

  90.       {  1,10, 1},{ -1,10, 1},{  1,11, 1},{ -1,11, 1},{  2, 1, 2},{ -2, 1, 2},

  91.       {  1,12, 1},{ -1,12, 1},{  1,13, 1},{ -1,13, 1},{  1,14, 1},{ -1,14, 1},

  92.       {  1,15, 1},{ -1,15, 1},{  2, 2, 2},{ -2, 2, 2},{  1,16, 1},{ -1,16, 1},

  93.       {  1,17, 1},{ -1,17, 1},{  3, 1, 3},{ -3, 1, 3},{  1,18, 1},{ -1,18, 1},

  94.       {  1,19, 1},{ -1,19, 1},{  2, 3, 2},{ -2, 3, 2},{  1,20, 1},{ -1,20, 1},

  95.       {  1,21, 1},{ -1,21, 1},{  2, 4, 2},{ -2, 4, 2},{  1,22, 1},{ -1,22, 1},

  96.       {  2, 5, 2},{ -2, 5, 2},{  1,23, 1},{ -1,23, 1},{   EOB   }

  97.     },

  98.     //level_add

  99.     { 0, 4, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  100.       2, 2, 2, 2, 2, 2, 2,-1,-1,-1},

  101.     2, //golomb_order

  102.     0, //inc_limit

  103.     23, //max_run

  104.   },{

  105.     { //level / run

  106.       {  1, 1, 0},{ -1, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  2, 1, 1},{ -2, 1, 1},

  107.       {  1, 3, 0},{ -1, 3, 0},{   EOB   },{  1, 4, 0},{ -1, 4, 0},{  1, 5, 0},

  108.       { -1, 5, 0},{  1, 6, 0},{ -1, 6, 0},{  3, 1, 2},{ -3, 1, 2},{  2, 2, 1},

  109.       { -2, 2, 1},{  1, 7, 0},{ -1, 7, 0},{  1, 8, 0},{ -1, 8, 0},{  1, 9, 0},

  110.       { -1, 9, 0},{  2, 3, 1},{ -2, 3, 1},{  4, 1, 2},{ -4, 1, 2},{  1,10, 0},

  111.       { -1,10, 0},{  1,11, 0},{ -1,11, 0},{  2, 4, 1},{ -2, 4, 1},{  3, 2, 2},

  112.       { -3, 2, 2},{  1,12, 0},{ -1,12, 0},{  2, 5, 1},{ -2, 5, 1},{  5, 1, 3},

  113.       { -5, 1, 3},{  1,13, 0},{ -1,13, 0},{  2, 6, 1},{ -2, 6, 1},{  1,14, 0},

  114.       { -1,14, 0},{  2, 7, 1},{ -2, 7, 1},{  2, 8, 1},{ -2, 8, 1},{  3, 3, 2},

  115.       { -3, 3, 2},{  6, 1, 3},{ -6, 1, 3},{  1,15, 0},{ -1,15, 0}

  116.     },

  117.     //level_add

  118.     { 0, 7, 4, 4, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2,-1,

  119.       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  120.     2, //golomb_order

  121.     1, //inc_limit

  122.     15, //max_run

  123.   },{

  124.     { //level / run

  125.       {  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  1, 2, 0},{ -1, 2, 0},

  126.       {  3, 1, 1},{ -3, 1, 1},{   EOB   },{  1, 3, 0},{ -1, 3, 0},{  2, 2, 0},

  127.       { -2, 2, 0},{  4, 1, 1},{ -4, 1, 1},{  1, 4, 0},{ -1, 4, 0},{  5, 1, 2},

  128.       { -5, 1, 2},{  1, 5, 0},{ -1, 5, 0},{  3, 2, 1},{ -3, 2, 1},{  2, 3, 0},

  129.       { -2, 3, 0},{  1, 6, 0},{ -1, 6, 0},{  6, 1, 2},{ -6, 1, 2},{  2, 4, 0},

  130.       { -2, 4, 0},{  1, 7, 0},{ -1, 7, 0},{  4, 2, 1},{ -4, 2, 1},{  7, 1, 2},

  131.       { -7, 1, 2},{  3, 3, 1},{ -3, 3, 1},{  2, 5, 0},{ -2, 5, 0},{  1, 8, 0},

  132.       { -1, 8, 0},{  2, 6, 0},{ -2, 6, 0},{  8, 1, 3},{ -8, 1, 3},{  1, 9, 0},

  133.       { -1, 9, 0},{  5, 2, 2},{ -5, 2, 2},{  3, 4, 1},{ -3, 4, 1},{  2, 7, 0},

  134.       { -2, 7, 0},{  9, 1, 3},{ -9, 1, 3},{  1,10, 0},{ -1,10, 0}

  135.     },

  136.     //level_add

  137.     { 0,10, 6, 4, 4, 3, 3, 3, 2, 2, 2,-1,-1,-1,-1,-1,-1,

  138.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  139.     2, //golomb_order

  140.     2, //inc_limit

  141.     10, //max_run

  142.   },{

  143.     { //level / run

  144.       {  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},{ -3, 1, 0},

  145.       {  1, 2, 0},{ -1, 2, 0},{   EOB   },{  4, 1, 0},{ -4, 1, 0},{  5, 1, 1},

  146.       { -5, 1, 1},{  2, 2, 0},{ -2, 2, 0},{  1, 3, 0},{ -1, 3, 0},{  6, 1, 1},

  147.       { -6, 1, 1},{  3, 2, 0},{ -3, 2, 0},{  7, 1, 1},{ -7, 1, 1},{  1, 4, 0},

  148.       { -1, 4, 0},{  8, 1, 2},{ -8, 1, 2},{  2, 3, 0},{ -2, 3, 0},{  4, 2, 0},

  149.       { -4, 2, 0},{  1, 5, 0},{ -1, 5, 0},{  9, 1, 2},{ -9, 1, 2},{  5, 2, 1},

  150.       { -5, 2, 1},{  2, 4, 0},{ -2, 4, 0},{ 10, 1, 2},{-10, 1, 2},{  3, 3, 0},

  151.       { -3, 3, 0},{  1, 6, 0},{ -1, 6, 0},{ 11, 1, 3},{-11, 1, 3},{  6, 2, 1},

  152.       { -6, 2, 1},{  1, 7, 0},{ -1, 7, 0},{  2, 5, 0},{ -2, 5, 0},{  3, 4, 0},

  153.       { -3, 4, 0},{ 12, 1, 3},{-12, 1, 3},{  4, 3, 0},{ -4, 3, 0}

  154.     },

  155.     //level_add

  156.     { 0,13, 7, 5, 4, 3, 2, 2,-1,-1,-1 -1,-1,-1,-1,-1,-1,

  157.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  158.     2, //golomb_order

  159.     4, //inc_limit

  160.     7, //max_run

  161.   },{

  162.     { //level / run

  163.       {  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},{ -3, 1, 0},

  164.       {   EOB   },{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  6, 1, 0},

  165.       { -6, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  7, 1, 0},{ -7, 1, 0},{  8, 1, 1},

  166.       { -8, 1, 1},{  2, 2, 0},{ -2, 2, 0},{  9, 1, 1},{ -9, 1, 1},{ 10, 1, 1},

  167.       {-10, 1, 1},{  1, 3, 0},{ -1, 3, 0},{  3, 2, 0},{ -3, 2, 0},{ 11, 1, 2},

  168.       {-11, 1, 2},{  4, 2, 0},{ -4, 2, 0},{ 12, 1, 2},{-12, 1, 2},{ 13, 1, 2},

  169.       {-13, 1, 2},{  5, 2, 0},{ -5, 2, 0},{  1, 4, 0},{ -1, 4, 0},{  2, 3, 0},

  170.       { -2, 3, 0},{ 14, 1, 2},{-14, 1, 2},{  6, 2, 0},{ -6, 2, 0},{ 15, 1, 2},

  171.       {-15, 1, 2},{ 16, 1, 2},{-16, 1, 2},{  3, 3, 0},{ -3, 3, 0},{  1, 5, 0},

  172.       { -1, 5, 0},{  7, 2, 0},{ -7, 2, 0},{ 17, 1, 2},{-17, 1, 2}

  173.     },

  174.     //level_add

  175.     { 0,18, 8, 4, 2, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  176.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  177.     2, //golomb_order

  178.     7, //inc_limit

  179.     5, //max_run

  180.   },{

  181.     { //level / run

  182.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  183.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  6, 1, 0},

  184.       { -6, 1, 0},{  7, 1, 0},{ -7, 1, 0},{  8, 1, 0},{ -8, 1, 0},{  9, 1, 0},

  185.       { -9, 1, 0},{ 10, 1, 0},{-10, 1, 0},{  1, 2, 0},{ -1, 2, 0},{ 11, 1, 1},

  186.       {-11, 1, 1},{ 12, 1, 1},{-12, 1, 1},{ 13, 1, 1},{-13, 1, 1},{  2, 2, 0},

  187.       { -2, 2, 0},{ 14, 1, 1},{-14, 1, 1},{ 15, 1, 1},{-15, 1, 1},{  3, 2, 0},

  188.       { -3, 2, 0},{ 16, 1, 1},{-16, 1, 1},{  1, 3, 0},{ -1, 3, 0},{ 17, 1, 1},

  189.       {-17, 1, 1},{  4, 2, 0},{ -4, 2, 0},{ 18, 1, 1},{-18, 1, 1},{  5, 2, 0},

  190.       { -5, 2, 0},{ 19, 1, 1},{-19, 1, 1},{ 20, 1, 1},{-20, 1, 1},{  6, 2, 0},

  191.       { -6, 2, 0},{ 21, 1, 1},{-21, 1, 1},{  2, 3, 0},{ -2, 3, 0}

  192.     },

  193.     //level_add

  194.     { 0,22, 7, 3,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  195.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  196.     2, //golomb_order

  197.     10, //inc_limit

  198.     3, //max_run

  199.   },{

  200.     { //level / run

  201.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  202.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  6, 1, 0},

  203.       { -6, 1, 0},{  7, 1, 0},{ -7, 1, 0},{  8, 1, 0},{ -8, 1, 0},{  9, 1, 0},

  204.       { -9, 1, 0},{ 10, 1, 0},{-10, 1, 0},{ 11, 1, 0},{-11, 1, 0},{ 12, 1, 0},

  205.       {-12, 1, 0},{ 13, 1, 0},{-13, 1, 0},{ 14, 1, 0},{-14, 1, 0},{ 15, 1, 0},

  206.       {-15, 1, 0},{ 16, 1, 0},{-16, 1, 0},{  1, 2, 0},{ -1, 2, 0},{ 17, 1, 0},

  207.       {-17, 1, 0},{ 18, 1, 0},{-18, 1, 0},{ 19, 1, 0},{-19, 1, 0},{ 20, 1, 0},

  208.       {-20, 1, 0},{ 21, 1, 0},{-21, 1, 0},{  2, 2, 0},{ -2, 2, 0},{ 22, 1, 0},

  209.       {-22, 1, 0},{ 23, 1, 0},{-23, 1, 0},{ 24, 1, 0},{-24, 1, 0},{ 25, 1, 0},

  210.       {-25, 1, 0},{  3, 2, 0},{ -3, 2, 0},{ 26, 1, 0},{-26, 1, 0}

  211.     },

  212.     //level_add

  213.     { 0,27, 4,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  214.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  215.     2, //golomb_order

  216.     INT_MAX, //inc_limit

  217.     2, //max_run

  218.   }

  219. };

  220. 

  221. static const struct dec_2dvlc inter_dec[7] = {

  222.   {

  223.     { //level / run

  224.       {  1, 1, 1},{ -1, 1, 1},{  1, 2, 1},{ -1, 2, 1},{  1, 3, 1},{ -1, 3, 1},

  225.       {  1, 4, 1},{ -1, 4, 1},{  1, 5, 1},{ -1, 5, 1},{  1, 6, 1},{ -1, 6, 1},

  226.       {  1, 7, 1},{ -1, 7, 1},{  1, 8, 1},{ -1, 8, 1},{  1, 9, 1},{ -1, 9, 1},

  227.       {  1,10, 1},{ -1,10, 1},{  1,11, 1},{ -1,11, 1},{  1,12, 1},{ -1,12, 1},

  228.       {  1,13, 1},{ -1,13, 1},{  2, 1, 2},{ -2, 1, 2},{  1,14, 1},{ -1,14, 1},

  229.       {  1,15, 1},{ -1,15, 1},{  1,16, 1},{ -1,16, 1},{  1,17, 1},{ -1,17, 1},

  230.       {  1,18, 1},{ -1,18, 1},{  1,19, 1},{ -1,19, 1},{  3, 1, 3},{ -3, 1, 3},

  231.       {  1,20, 1},{ -1,20, 1},{  1,21, 1},{ -1,21, 1},{  2, 2, 2},{ -2, 2, 2},

  232.       {  1,22, 1},{ -1,22, 1},{  1,23, 1},{ -1,23, 1},{  1,24, 1},{ -1,24, 1},

  233.       {  1,25, 1},{ -1,25, 1},{  1,26, 1},{ -1,26, 1},{   EOB   }

  234.     },

  235.     //level_add

  236.     { 0, 4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  237.       2, 2, 2, 2, 2, 2, 2, 2, 2, 2},

  238.     3, //golomb_order

  239.     0, //inc_limit

  240.     26 //max_run

  241.   },{

  242.     { //level / run

  243.       {  1, 1, 0},{ -1, 1, 0},{   EOB   },{  1, 2, 0},{ -1, 2, 0},{  1, 3, 0},

  244.       { -1, 3, 0},{  1, 4, 0},{ -1, 4, 0},{  1, 5, 0},{ -1, 5, 0},{  1, 6, 0},

  245.       { -1, 6, 0},{  2, 1, 1},{ -2, 1, 1},{  1, 7, 0},{ -1, 7, 0},{  1, 8, 0},

  246.       { -1, 8, 0},{  1, 9, 0},{ -1, 9, 0},{  1,10, 0},{ -1,10, 0},{  2, 2, 1},

  247.       { -2, 2, 1},{  1,11, 0},{ -1,11, 0},{  1,12, 0},{ -1,12, 0},{  3, 1, 2},

  248.       { -3, 1, 2},{  1,13, 0},{ -1,13, 0},{  1,14, 0},{ -1,14, 0},{  2, 3, 1},

  249.       { -2, 3, 1},{  1,15, 0},{ -1,15, 0},{  2, 4, 1},{ -2, 4, 1},{  1,16, 0},

  250.       { -1,16, 0},{  2, 5, 1},{ -2, 5, 1},{  1,17, 0},{ -1,17, 0},{  4, 1, 3},

  251.       { -4, 1, 3},{  2, 6, 1},{ -2, 6, 1},{  1,18, 0},{ -1,18, 0},{  1,19, 0},

  252.       { -1,19, 0},{  2, 7, 1},{ -2, 7, 1},{  3, 2, 2},{ -3, 2, 2}

  253.     },

  254.     //level_add

  255.     { 0, 5, 4, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  256.       2, 2, 2,-1,-1,-1,-1,-1,-1,-1},

  257.     2, //golomb_order

  258.     1, //inc_limit

  259.     19 //max_run

  260.   },{

  261.     { //level / run

  262.       {  1, 1, 0},{ -1, 1, 0},{   EOB   },{  1, 2, 0},{ -1, 2, 0},{  2, 1, 0},

  263.       { -2, 1, 0},{  1, 3, 0},{ -1, 3, 0},{  1, 4, 0},{ -1, 4, 0},{  3, 1, 1},

  264.       { -3, 1, 1},{  2, 2, 0},{ -2, 2, 0},{  1, 5, 0},{ -1, 5, 0},{  1, 6, 0},

  265.       { -1, 6, 0},{  1, 7, 0},{ -1, 7, 0},{  2, 3, 0},{ -2, 3, 0},{  4, 1, 2},

  266.       { -4, 1, 2},{  1, 8, 0},{ -1, 8, 0},{  3, 2, 1},{ -3, 2, 1},{  2, 4, 0},

  267.       { -2, 4, 0},{  1, 9, 0},{ -1, 9, 0},{  1,10, 0},{ -1,10, 0},{  5, 1, 2},

  268.       { -5, 1, 2},{  2, 5, 0},{ -2, 5, 0},{  1,11, 0},{ -1,11, 0},{  2, 6, 0},

  269.       { -2, 6, 0},{  1,12, 0},{ -1,12, 0},{  3, 3, 1},{ -3, 3, 1},{  6, 1, 2},

  270.       { -6, 1, 2},{  4, 2, 2},{ -4, 2, 2},{  1,13, 0},{ -1,13, 0},{  2, 7, 0},

  271.       { -2, 7, 0},{  3, 4, 1},{ -3, 4, 1},{  1,14, 0},{ -1,14, 0}

  272.     },

  273.     //level_add

  274.     { 0, 7, 5, 4, 4, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2,-1,-1,

  275.       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  276.     2, //golomb_order

  277.     2, //inc_limit

  278.     14 //max_run

  279.   },{

  280.     { //level / run

  281.       {  1, 1, 0},{ -1, 1, 0},{   EOB   },{  2, 1, 0},{ -2, 1, 0},{  1, 2, 0},

  282.       { -1, 2, 0},{  3, 1, 0},{ -3, 1, 0},{  1, 3, 0},{ -1, 3, 0},{  2, 2, 0},

  283.       { -2, 2, 0},{  4, 1, 1},{ -4, 1, 1},{  1, 4, 0},{ -1, 4, 0},{  5, 1, 1},

  284.       { -5, 1, 1},{  1, 5, 0},{ -1, 5, 0},{  3, 2, 0},{ -3, 2, 0},{  2, 3, 0},

  285.       { -2, 3, 0},{  1, 6, 0},{ -1, 6, 0},{  6, 1, 1},{ -6, 1, 1},{  2, 4, 0},

  286.       { -2, 4, 0},{  1, 7, 0},{ -1, 7, 0},{  4, 2, 1},{ -4, 2, 1},{  7, 1, 2},

  287.       { -7, 1, 2},{  3, 3, 0},{ -3, 3, 0},{  1, 8, 0},{ -1, 8, 0},{  2, 5, 0},

  288.       { -2, 5, 0},{  8, 1, 2},{ -8, 1, 2},{  1, 9, 0},{ -1, 9, 0},{  3, 4, 0},

  289.       { -3, 4, 0},{  2, 6, 0},{ -2, 6, 0},{  5, 2, 1},{ -5, 2, 1},{  1,10, 0},

  290.       { -1,10, 0},{  9, 1, 2},{ -9, 1, 2},{  4, 3, 1},{ -4, 3, 1}

  291.     },

  292.     //level_add

  293.     { 0,10, 6, 5, 4, 3, 3, 2, 2, 2, 2,-1,-1,-1,-1,-1,-1,

  294.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  295.     2, //golomb_order

  296.     3, //inc_limit

  297.     10 //max_run

  298.   },{

  299.     { //level / run

  300.       {  1, 1, 0},{ -1, 1, 0},{   EOB   },{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  301.       { -3, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},

  302.       { -5, 1, 0},{  2, 2, 0},{ -2, 2, 0},{  1, 3, 0},{ -1, 3, 0},{  6, 1, 0},

  303.       { -6, 1, 0},{  3, 2, 0},{ -3, 2, 0},{  7, 1, 1},{ -7, 1, 1},{  1, 4, 0},

  304.       { -1, 4, 0},{  8, 1, 1},{ -8, 1, 1},{  2, 3, 0},{ -2, 3, 0},{  4, 2, 0},

  305.       { -4, 2, 0},{  1, 5, 0},{ -1, 5, 0},{  9, 1, 1},{ -9, 1, 1},{  5, 2, 0},

  306.       { -5, 2, 0},{  2, 4, 0},{ -2, 4, 0},{  1, 6, 0},{ -1, 6, 0},{ 10, 1, 2},

  307.       {-10, 1, 2},{  3, 3, 0},{ -3, 3, 0},{ 11, 1, 2},{-11, 1, 2},{  1, 7, 0},

  308.       { -1, 7, 0},{  6, 2, 0},{ -6, 2, 0},{  3, 4, 0},{ -3, 4, 0},{  2, 5, 0},

  309.       { -2, 5, 0},{ 12, 1, 2},{-12, 1, 2},{  4, 3, 0},{ -4, 3, 0}

  310.     },

  311.     //level_add

  312.     { 0,13, 7, 5, 4, 3, 2, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  313.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  314.     2, //golomb_order

  315.     6, //inc_limit

  316.     7  //max_run

  317.   },{

  318.     { //level / run

  319.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  320.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  1, 2, 0},

  321.       { -1, 2, 0},{  6, 1, 0},{ -6, 1, 0},{  7, 1, 0},{ -7, 1, 0},{  8, 1, 0},

  322.       { -8, 1, 0},{  2, 2, 0},{ -2, 2, 0},{  9, 1, 0},{ -9, 1, 0},{  1, 3, 0},

  323.       { -1, 3, 0},{ 10, 1, 1},{-10, 1, 1},{  3, 2, 0},{ -3, 2, 0},{ 11, 1, 1},

  324.       {-11, 1, 1},{  4, 2, 0},{ -4, 2, 0},{ 12, 1, 1},{-12, 1, 1},{  1, 4, 0},

  325.       { -1, 4, 0},{  2, 3, 0},{ -2, 3, 0},{ 13, 1, 1},{-13, 1, 1},{  5, 2, 0},

  326.       { -5, 2, 0},{ 14, 1, 1},{-14, 1, 1},{  6, 2, 0},{ -6, 2, 0},{  1, 5, 0},

  327.       { -1, 5, 0},{ 15, 1, 1},{-15, 1, 1},{  3, 3, 0},{ -3, 3, 0},{ 16, 1, 1},

  328.       {-16, 1, 1},{  2, 4, 0},{ -2, 4, 0},{  7, 2, 0},{ -7, 2, 0}

  329.     },

  330.     //level_add

  331.     { 0,17, 8, 4, 3, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  332.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  333.     2, //golomb_order

  334.     9, //inc_limit

  335.     5  //max_run

  336.   },{

  337.     { //level / run

  338.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  339.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  6, 1, 0},

  340.       { -6, 1, 0},{  7, 1, 0},{ -7, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  8, 1, 0},

  341.       { -8, 1, 0},{  9, 1, 0},{ -9, 1, 0},{ 10, 1, 0},{-10, 1, 0},{ 11, 1, 0},

  342.       {-11, 1, 0},{ 12, 1, 0},{-12, 1, 0},{  2, 2, 0},{ -2, 2, 0},{ 13, 1, 0},

  343.       {-13, 1, 0},{  1, 3, 0},{ -1, 3, 0},{ 14, 1, 0},{-14, 1, 0},{ 15, 1, 0},

  344.       {-15, 1, 0},{  3, 2, 0},{ -3, 2, 0},{ 16, 1, 0},{-16, 1, 0},{ 17, 1, 0},

  345.       {-17, 1, 0},{ 18, 1, 0},{-18, 1, 0},{  4, 2, 0},{ -4, 2, 0},{ 19, 1, 0},

  346.       {-19, 1, 0},{ 20, 1, 0},{-20, 1, 0},{  2, 3, 0},{ -2, 3, 0},{  1, 4, 0},

  347.       { -1, 4, 0},{  5, 2, 0},{ -5, 2, 0},{ 21, 1, 0},{-21, 1, 0}

  348.     },

  349.     //level_add

  350.     { 0,22, 6, 3, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  351.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  352.     2, //golomb_order

  353.     INT_MAX, //inc_limit

  354.     4 //max_run

  355.   }

  356. };

  357. 

  358. static const struct dec_2dvlc chroma_dec[5] = {

  359.   {

  360.     { //level / run

  361.       {  1, 1, 1},{ -1, 1, 1},{  1, 2, 1},{ -1, 2, 1},{  1, 3, 1},{ -1, 3, 1},

  362.       {  1, 4, 1},{ -1, 4, 1},{  1, 5, 1},{ -1, 5, 1},{  1, 6, 1},{ -1, 6, 1},

  363.       {  1, 7, 1},{ -1, 7, 1},{  2, 1, 2},{ -2, 1, 2},{  1, 8, 1},{ -1, 8, 1},

  364.       {  1, 9, 1},{ -1, 9, 1},{  1,10, 1},{ -1,10, 1},{  1,11, 1},{ -1,11, 1},

  365.       {  1,12, 1},{ -1,12, 1},{  1,13, 1},{ -1,13, 1},{  1,14, 1},{ -1,14, 1},

  366.       {  1,15, 1},{ -1,15, 1},{  3, 1, 3},{ -3, 1, 3},{  1,16, 1},{ -1,16, 1},

  367.       {  1,17, 1},{ -1,17, 1},{  1,18, 1},{ -1,18, 1},{  1,19, 1},{ -1,19, 1},

  368.       {  1,20, 1},{ -1,20, 1},{  1,21, 1},{ -1,21, 1},{  1,22, 1},{ -1,22, 1},

  369.       {  2, 2, 2},{ -2, 2, 2},{  1,23, 1},{ -1,23, 1},{  1,24, 1},{ -1,24, 1},

  370.       {  1,25, 1},{ -1,25, 1},{  4, 1, 3},{ -4, 1, 3},{   EOB   }

  371.     },

  372.     //level_add

  373.     { 0, 5, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  374.       2, 2, 2, 2, 2, 2, 2, 2, 2,-1},

  375.     2, //golomb_order

  376.     0, //inc_limit

  377.     25 //max_run

  378.   },{

  379.     { //level / run

  380.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  2, 1, 1},

  381.       { -2, 1, 1},{  1, 3, 0},{ -1, 3, 0},{  1, 4, 0},{ -1, 4, 0},{  1, 5, 0},

  382.       { -1, 5, 0},{  1, 6, 0},{ -1, 6, 0},{  3, 1, 2},{ -3, 1, 2},{  1, 7, 0},

  383.       { -1, 7, 0},{  1, 8, 0},{ -1, 8, 0},{  2, 2, 1},{ -2, 2, 1},{  1, 9, 0},

  384.       { -1, 9, 0},{  1,10, 0},{ -1,10, 0},{  1,11, 0},{ -1,11, 0},{  4, 1, 2},

  385.       { -4, 1, 2},{  1,12, 0},{ -1,12, 0},{  1,13, 0},{ -1,13, 0},{  1,14, 0},

  386.       { -1,14, 0},{  2, 3, 1},{ -2, 3, 1},{  1,15, 0},{ -1,15, 0},{  2, 4, 1},

  387.       { -2, 4, 1},{  5, 1, 3},{ -5, 1, 3},{  3, 2, 2},{ -3, 2, 2},{  1,16, 0},

  388.       { -1,16, 0},{  1,17, 0},{ -1,17, 0},{  1,18, 0},{ -1,18, 0},{  2, 5, 1},

  389.       { -2, 5, 1},{  1,19, 0},{ -1,19, 0},{  1,20, 0},{ -1,20, 0}

  390.     },

  391.     //level_add

  392.     { 0, 6, 4, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,

  393.       2, 2, 2, 2,-1,-1,-1,-1,-1,-1},

  394.     0, //golomb_order

  395.     1, //inc_limit

  396.     20 //max_run

  397.   },{

  398.     { //level / run

  399.       {  1, 1, 0},{ -1, 1, 0},{   EOB   },{  2, 1, 0},{ -2, 1, 0},{  1, 2, 0},

  400.       { -1, 2, 0},{  3, 1, 1},{ -3, 1, 1},{  1, 3, 0},{ -1, 3, 0},{  4, 1, 1},

  401.       { -4, 1, 1},{  2, 2, 0},{ -2, 2, 0},{  1, 4, 0},{ -1, 4, 0},{  5, 1, 2},

  402.       { -5, 1, 2},{  1, 5, 0},{ -1, 5, 0},{  3, 2, 1},{ -3, 2, 1},{  2, 3, 0},

  403.       { -2, 3, 0},{  1, 6, 0},{ -1, 6, 0},{  6, 1, 2},{ -6, 1, 2},{  1, 7, 0},

  404.       { -1, 7, 0},{  2, 4, 0},{ -2, 4, 0},{  7, 1, 2},{ -7, 1, 2},{  1, 8, 0},

  405.       { -1, 8, 0},{  4, 2, 1},{ -4, 2, 1},{  1, 9, 0},{ -1, 9, 0},{  3, 3, 1},

  406.       { -3, 3, 1},{  2, 5, 0},{ -2, 5, 0},{  2, 6, 0},{ -2, 6, 0},{  8, 1, 2},

  407.       { -8, 1, 2},{  1,10, 0},{ -1,10, 0},{  1,11, 0},{ -1,11, 0},{  9, 1, 2},

  408.       { -9, 1, 2},{  5, 2, 2},{ -5, 2, 2},{  3, 4, 1},{ -3, 4, 1},

  409.     },

  410.     //level_add

  411.     { 0,10, 6, 4, 4, 3, 3, 2, 2, 2, 2, 2,-1,-1,-1,-1,-1,

  412.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  413.     1, //golomb_order

  414.     2, //inc_limit

  415.     11 //max_run

  416.   },{

  417.     { //level / run

  418.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  419.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  1, 2, 0},{ -1, 2, 0},{  5, 1, 1},

  420.       { -5, 1, 1},{  2, 2, 0},{ -2, 2, 0},{  6, 1, 1},{ -6, 1, 1},{  1, 3, 0},

  421.       { -1, 3, 0},{  7, 1, 1},{ -7, 1, 1},{  3, 2, 0},{ -3, 2, 0},{  8, 1, 1},

  422.       { -8, 1, 1},{  1, 4, 0},{ -1, 4, 0},{  2, 3, 0},{ -2, 3, 0},{  9, 1, 1},

  423.       { -9, 1, 1},{  4, 2, 0},{ -4, 2, 0},{  1, 5, 0},{ -1, 5, 0},{ 10, 1, 1},

  424.       {-10, 1, 1},{  3, 3, 0},{ -3, 3, 0},{  5, 2, 1},{ -5, 2, 1},{  2, 4, 0},

  425.       { -2, 4, 0},{ 11, 1, 1},{-11, 1, 1},{  1, 6, 0},{ -1, 6, 0},{ 12, 1, 1},

  426.       {-12, 1, 1},{  1, 7, 0},{ -1, 7, 0},{  6, 2, 1},{ -6, 2, 1},{ 13, 1, 1},

  427.       {-13, 1, 1},{  2, 5, 0},{ -2, 5, 0},{  1, 8, 0},{ -1, 8, 0},

  428.     },

  429.     //level_add

  430.     { 0,14, 7, 4, 3, 3, 2, 2, 2,-1,-1,-1,-1,-1,-1,-1,-1,

  431.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  432.     1, //golomb_order

  433.     4, //inc_limit

  434.     8  //max_run

  435.   },{

  436.     { //level / run

  437.       {   EOB   },{  1, 1, 0},{ -1, 1, 0},{  2, 1, 0},{ -2, 1, 0},{  3, 1, 0},

  438.       { -3, 1, 0},{  4, 1, 0},{ -4, 1, 0},{  5, 1, 0},{ -5, 1, 0},{  6, 1, 0},

  439.       { -6, 1, 0},{  7, 1, 0},{ -7, 1, 0},{  8, 1, 0},{ -8, 1, 0},{  1, 2, 0},

  440.       { -1, 2, 0},{  9, 1, 0},{ -9, 1, 0},{ 10, 1, 0},{-10, 1, 0},{ 11, 1, 0},

  441.       {-11, 1, 0},{  2, 2, 0},{ -2, 2, 0},{ 12, 1, 0},{-12, 1, 0},{ 13, 1, 0},

  442.       {-13, 1, 0},{  3, 2, 0},{ -3, 2, 0},{ 14, 1, 0},{-14, 1, 0},{  1, 3, 0},

  443.       { -1, 3, 0},{ 15, 1, 0},{-15, 1, 0},{  4, 2, 0},{ -4, 2, 0},{ 16, 1, 0},

  444.       {-16, 1, 0},{ 17, 1, 0},{-17, 1, 0},{  5, 2, 0},{ -5, 2, 0},{  1, 4, 0},

  445.       { -1, 4, 0},{  2, 3, 0},{ -2, 3, 0},{ 18, 1, 0},{-18, 1, 0},{  6, 2, 0},

  446.       { -6, 2, 0},{ 19, 1, 0},{-19, 1, 0},{  1, 5, 0},{ -1, 5, 0},

  447.     },

  448.     //level_add

  449.     { 0,20, 7, 3, 2, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,

  450.      -1,-1,-1,-1,-1,-1,-1,-1,-1,-1},

  451.     0, //golomb_order

  452.     INT_MAX, //inc_limit

  453.     5, //max_run

  454.   }

  455. };

  456. 

  457. #undef EOB

  458. 

  459. /*****************************************************************************

  460.  *

  461.  * motion vector prediction

  462.  *

  463.  ****************************************************************************/

  464. 

  465. static inline void store_mvs(AVSContext *h) {

  466.     h->col_mv[h->mbidx*4 + 0] = h->mv[MV_FWD_X0];

  467.     h->col_mv[h->mbidx*4 + 1] = h->mv[MV_FWD_X1];

  468.     h->col_mv[h->mbidx*4 + 2] = h->mv[MV_FWD_X2];

  469.     h->col_mv[h->mbidx*4 + 3] = h->mv[MV_FWD_X3];

  470. }

  471. 

  472. static inline void mv_pred_direct(AVSContext *h, cavs_vector *pmv_fw,

  473.                                   cavs_vector *col_mv) {

  474.     cavs_vector *pmv_bw = pmv_fw + MV_BWD_OFFS;

  475.     int den = h->direct_den[col_mv->ref];

  476.     int m = col_mv->x >> 31;

  477. 

  478.     pmv_fw->dist = h->dist[1];

  479.     pmv_bw->dist = h->dist[0];

  480.     pmv_fw->ref = 1;

  481.     pmv_bw->ref = 0;

  482.     /* scale the co-located motion vector according to its temporal span */

  483.     pmv_fw->x = (((den+(den*col_mv->x*pmv_fw->dist^m)-m-1)>>14)^m)-m;

  484.     pmv_bw->x = m-(((den+(den*col_mv->x*pmv_bw->dist^m)-m-1)>>14)^m);

  485.     m = col_mv->y >> 31;

  486.     pmv_fw->y = (((den+(den*col_mv->y*pmv_fw->dist^m)-m-1)>>14)^m)-m;

  487.     pmv_bw->y = m-(((den+(den*col_mv->y*pmv_bw->dist^m)-m-1)>>14)^m);

  488. }

  489. 

  490. static inline void mv_pred_sym(AVSContext *h, cavs_vector *src, enum cavs_block size) {

  491.     cavs_vector *dst = src + MV_BWD_OFFS;

  492. 

  493.     /* backward mv is the scaled and negated forward mv */

  494.     dst->x = -((src->x * h->sym_factor + 256) >> 9);

  495.     dst->y = -((src->y * h->sym_factor + 256) >> 9);

  496.     dst->ref = 0;

  497.     dst->dist = h->dist[0];

  498.     set_mvs(dst, size);

  499. }

  500. 

  501. /*****************************************************************************

  502.  *

  503.  * residual data decoding

  504.  *

  505.  ****************************************************************************/

  506. 

  507. /** kth-order exponential golomb code */

  508. static inline int get_ue_code(GetBitContext *gb, int order) {

  509.     if(order) {

  510.         int ret = get_ue_golomb(gb) << order;

  511.         return ret + get_bits(gb,order);

  512.     }

  513.     return get_ue_golomb(gb);

  514. }

  515. 

  516. static inline int dequant(AVSContext *h, DCTELEM *level_buf, uint8_t *run_buf,

  517.                           DCTELEM *dst, int mul, int shift, int coeff_num) {

  518.     int round = 1 << (shift - 1);

  519.     int pos = -1;

  520.     const uint8_t *scantab = h->scantable.permutated;

  521. 

  522.     /* inverse scan and dequantization */

  523.     while(--coeff_num >= 0){

  524.         pos += run_buf[coeff_num];

  525.         if(pos > 63) {

  526.             av_log(h->s.avctx, AV_LOG_ERROR,

  527.                 "position out of block bounds at pic %d MB(%d,%d)\n",

  528.                 h->picture.poc, h->mbx, h->mby);

  529.             return -1;

  530.         }

  531.         dst[scantab[pos]] = (level_buf[coeff_num]*mul + round) >> shift;

  532.     }

  533.     return 0;

  534. }

  535. 

  536. /**

  537.  * decode coefficients from one 8x8 block, dequantize, inverse transform

  538.  *  and add them to sample block

  539.  * @param r pointer to 2D VLC table

  540.  * @param esc_golomb_order escape codes are k-golomb with this order k

  541.  * @param qp quantizer

  542.  * @param dst location of sample block

  543.  * @param stride line stride in frame buffer

  544.  */

  545. static int decode_residual_block(AVSContext *h, GetBitContext *gb,

  546.                                  const struct dec_2dvlc *r, int esc_golomb_order,

  547.                                  int qp, uint8_t *dst, int stride) {

  548.     int i, esc_code, level, mask;

  549.     unsigned int level_code, run;

  550.     DCTELEM level_buf[65];

  551.     uint8_t run_buf[65];

  552.     DCTELEM *block = h->block;

  553. 

  554.     for(i=0;i<65;i++) {

  555.         level_code = get_ue_code(gb,r->golomb_order);

  556.         if(level_code >= ESCAPE_CODE) {

  557.             run = ((level_code - ESCAPE_CODE) >> 1) + 1;

  558.             if(run > 64)

  559.                 return -1;

  560.             esc_code = get_ue_code(gb,esc_golomb_order);

  561.             level = esc_code + (run > r->max_run ? 1 : r->level_add[run]);

  562.             while(level > r->inc_limit)

  563.                 r++;

  564.             mask = -(level_code & 1);

  565.             level = (level^mask) - mask;

  566.         } else {

  567.             level = r->rltab[level_code][0];

  568.             if(!level) //end of block signal

  569.                 break;

  570.             run   = r->rltab[level_code][1];

  571.             r += r->rltab[level_code][2];

  572.         }

  573.         level_buf[i] = level;

  574.         run_buf[i] = run;

  575.     }

  576.     if (dequant(h, level_buf, run_buf, block, dequant_mul[qp],

  577.                 dequant_shift[qp], i))

  578.         return -1;

  579.     h->cdsp.cavs_idct8_add(dst,block,stride);

  580.     h->s.dsp.clear_block(block);

  581.     return 0;

  582. }

  583. 

  584. 

  585. static inline void decode_residual_chroma(AVSContext *h) {

  586.     if(h->cbp & (1<<4))

  587.         decode_residual_block(h, &h->s.gb, chroma_dec, 0,

  588.                               cavs_chroma_qp[h->qp], h->cu, h->c_stride);

  589.     if(h->cbp & (1<<5))

  590.         decode_residual_block(h, &h->s.gb, chroma_dec, 0,

  591.                               cavs_chroma_qp[h->qp], h->cv, h->c_stride);

  592. }

  593. 

  594. static inline int decode_residual_inter(AVSContext *h) {

  595.     int block;

  596. 

  597.     /* get coded block pattern */

  598.     int cbp= get_ue_golomb(&h->s.gb);

  599.     if(cbp > 63U){

  600.         av_log(h->s.avctx, AV_LOG_ERROR, "illegal inter cbp\n");

  601.         return -1;

  602.     }

  603.     h->cbp = cbp_tab[cbp][1];

  604. 

  605.     /* get quantizer */

  606.     if(h->cbp && !h->qp_fixed)

  607.         h->qp = (h->qp + get_se_golomb(&h->s.gb)) & 63;

  608.     for(block=0;block<4;block++)

  609.         if(h->cbp & (1<<block))

  610.             decode_residual_block(h, &h->s.gb, inter_dec, 0, h->qp,

  611.                                   h->cy + h->luma_scan[block], h->l_stride);

  612.     decode_residual_chroma(h);

  613. 

  614.     return 0;

  615. }

  616. 

  617. /*****************************************************************************

  618.  *

  619.  * macroblock level

  620.  *

  621.  ****************************************************************************/

  622. 

  623. static inline void set_mv_intra(AVSContext *h) {

  624.     h->mv[MV_FWD_X0] = ff_cavs_intra_mv;

  625.     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);

  626.     h->mv[MV_BWD_X0] = ff_cavs_intra_mv;

  627.     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

  628.     if(h->pic_type != AV_PICTURE_TYPE_B)

  629.         h->col_type_base[h->mbidx] = I_8X8;

  630. }

  631. 

  632. static int decode_mb_i(AVSContext *h, int cbp_code) {

  633.     GetBitContext *gb = &h->s.gb;

  634.     unsigned pred_mode_uv;

  635.     int block;

  636.     uint8_t top[18];

  637.     uint8_t *left = NULL;

  638.     uint8_t *d;

  639. 

  640.     ff_cavs_init_mb(h);

  641. 

  642.     /* get intra prediction modes from stream */

  643.     for(block=0;block<4;block++) {

  644.         int nA,nB,predpred;

  645.         int pos = scan3x3[block];

  646. 

  647.         nA = h->pred_mode_Y[pos-1];

  648.         nB = h->pred_mode_Y[pos-3];

  649.         predpred = FFMIN(nA,nB);

  650.         if(predpred == NOT_AVAIL) // if either is not available

  651.             predpred = INTRA_L_LP;

  652.         if(!get_bits1(gb)){

  653.             int rem_mode= get_bits(gb, 2);

  654.             predpred = rem_mode + (rem_mode >= predpred);

  655.         }

  656.         h->pred_mode_Y[pos] = predpred;

  657.     }

  658.     pred_mode_uv = get_ue_golomb(gb);

  659.     if(pred_mode_uv > 6) {

  660.         av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra chroma pred mode\n");

  661.         return -1;

  662.     }

  663.     ff_cavs_modify_mb_i(h, &pred_mode_uv);

  664. 

  665.     /* get coded block pattern */

  666.     if(h->pic_type == AV_PICTURE_TYPE_I)

  667.         cbp_code = get_ue_golomb(gb);

  668.     if(cbp_code > 63U){

  669.         av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra cbp\n");

  670.         return -1;

  671.     }

  672.     h->cbp = cbp_tab[cbp_code][0];

  673.     if(h->cbp && !h->qp_fixed)

  674.         h->qp = (h->qp + get_se_golomb(gb)) & 63; //qp_delta

  675. 

  676.     /* luma intra prediction interleaved with residual decode/transform/add */

  677.     for(block=0;block<4;block++) {

  678.         d = h->cy + h->luma_scan[block];

  679.         ff_cavs_load_intra_pred_luma(h, top, &left, block);

  680.         h->intra_pred_l[h->pred_mode_Y[scan3x3[block]]]

  681.             (d, top, left, h->l_stride);

  682.         if(h->cbp & (1<<block))

  683.             decode_residual_block(h, gb, intra_dec, 1, h->qp, d, h->l_stride);

  684.     }

  685. 

  686.     /* chroma intra prediction */

  687.     ff_cavs_load_intra_pred_chroma(h);

  688.     h->intra_pred_c[pred_mode_uv](h->cu, &h->top_border_u[h->mbx*10],

  689.                                   h->left_border_u, h->c_stride);

  690.     h->intra_pred_c[pred_mode_uv](h->cv, &h->top_border_v[h->mbx*10],

  691.                                   h->left_border_v, h->c_stride);

  692. 

  693.     decode_residual_chroma(h);

  694.     ff_cavs_filter(h,I_8X8);

  695.     set_mv_intra(h);

  696.     return 0;

  697. }

  698. 

  699. static inline void set_intra_mode_default(AVSContext *h) {

  700.     if(h->stream_revision > 0) {

  701.         h->pred_mode_Y[3] =  h->pred_mode_Y[6] = NOT_AVAIL;

  702.         h->top_pred_Y[h->mbx*2+0] = h->top_pred_Y[h->mbx*2+1] = NOT_AVAIL;

  703.     } else {

  704.         h->pred_mode_Y[3] =  h->pred_mode_Y[6] = INTRA_L_LP;

  705.         h->top_pred_Y[h->mbx*2+0] = h->top_pred_Y[h->mbx*2+1] = INTRA_L_LP;

  706.     }

  707. }

  708. 

  709. static void decode_mb_p(AVSContext *h, enum cavs_mb mb_type) {

  710.     GetBitContext *gb = &h->s.gb;

  711.     int ref[4];

  712. 

  713.     ff_cavs_init_mb(h);

  714.     switch(mb_type) {

  715.     case P_SKIP:

  716.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_PSKIP,  BLK_16X16, 0);

  717.         break;

  718.     case P_16X16:

  719.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  720.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16,ref[0]);

  721.         break;

  722.     case P_16X8:

  723.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  724.         ref[2] = h->ref_flag ? 0 : get_bits1(gb);

  725.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP,    BLK_16X8, ref[0]);

  726.         ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT,   BLK_16X8, ref[2]);

  727.         break;

  728.     case P_8X16:

  729.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  730.         ref[1] = h->ref_flag ? 0 : get_bits1(gb);

  731.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT,   BLK_8X16, ref[0]);

  732.         ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, ref[1]);

  733.         break;

  734.     case P_8X8:

  735.         ref[0] = h->ref_flag ? 0 : get_bits1(gb);

  736.         ref[1] = h->ref_flag ? 0 : get_bits1(gb);

  737.         ref[2] = h->ref_flag ? 0 : get_bits1(gb);

  738.         ref[3] = h->ref_flag ? 0 : get_bits1(gb);

  739.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_MEDIAN,   BLK_8X8, ref[0]);

  740.         ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_MEDIAN,   BLK_8X8, ref[1]);

  741.         ff_cavs_mv(h, MV_FWD_X2, MV_FWD_X1, MV_PRED_MEDIAN,   BLK_8X8, ref[2]);

  742.         ff_cavs_mv(h, MV_FWD_X3, MV_FWD_X0, MV_PRED_MEDIAN,   BLK_8X8, ref[3]);

  743.     }

  744.     ff_cavs_inter(h, mb_type);

  745.     set_intra_mode_default(h);

  746.     store_mvs(h);

  747.     if(mb_type != P_SKIP)

  748.         decode_residual_inter(h);

  749.     ff_cavs_filter(h,mb_type);

  750.     h->col_type_base[h->mbidx] = mb_type;

  751. }

  752. 

  753. static int decode_mb_b(AVSContext *h, enum cavs_mb mb_type) {

  754.     int block;

  755.     enum cavs_sub_mb sub_type[4];

  756.     int flags;

  757. 

  758.     ff_cavs_init_mb(h);

  759. 

  760.     /* reset all MVs */

  761.     h->mv[MV_FWD_X0] = ff_cavs_dir_mv;

  762.     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);

  763.     h->mv[MV_BWD_X0] = ff_cavs_dir_mv;

  764.     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

  765.     switch(mb_type) {

  766.     case B_SKIP:

  767.     case B_DIRECT:

  768.         if(!h->col_type_base[h->mbidx]) {

  769.             /* intra MB at co-location, do in-plane prediction */

  770.             ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_BSKIP, BLK_16X16, 1);

  771.             ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_BSKIP, BLK_16X16, 0);

  772.         } else

  773.             /* direct prediction from co-located P MB, block-wise */

  774.             for(block=0;block<4;block++)

  775.                 mv_pred_direct(h,&h->mv[mv_scan[block]],

  776.                                  &h->col_mv[h->mbidx*4 + block]);

  777.         break;

  778.     case B_FWD_16X16:

  779.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);

  780.         break;

  781.     case B_SYM_16X16:

  782.         ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);

  783.         mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X16);

  784.         break;

  785.     case B_BWD_16X16:

  786.         ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_MEDIAN, BLK_16X16, 0);

  787.         break;

  788.     case B_8X8:

  789.         for(block=0;block<4;block++)

  790.             sub_type[block] = get_bits(&h->s.gb,2);

  791.         for(block=0;block<4;block++) {

  792.             switch(sub_type[block]) {

  793.             case B_SUB_DIRECT:

  794.                 if(!h->col_type_base[h->mbidx]) {

  795.                     /* intra MB at co-location, do in-plane prediction */

  796.                     ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,

  797.                             MV_PRED_BSKIP, BLK_8X8, 1);

  798.                     ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,

  799.                             mv_scan[block]-3+MV_BWD_OFFS,

  800.                             MV_PRED_BSKIP, BLK_8X8, 0);

  801.                 } else

  802.                     mv_pred_direct(h,&h->mv[mv_scan[block]],

  803.                                    &h->col_mv[h->mbidx*4 + block]);

  804.                 break;

  805.             case B_SUB_FWD:

  806.                 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,

  807.                         MV_PRED_MEDIAN, BLK_8X8, 1);

  808.                 break;

  809.             case B_SUB_SYM:

  810.                 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,

  811.                         MV_PRED_MEDIAN, BLK_8X8, 1);

  812.                 mv_pred_sym(h, &h->mv[mv_scan[block]], BLK_8X8);

  813.                 break;

  814.             }

  815.         }

  816.         for(block=0;block<4;block++) {

  817.             if(sub_type[block] == B_SUB_BWD)

  818.                 ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,

  819.                         mv_scan[block]+MV_BWD_OFFS-3,

  820.                         MV_PRED_MEDIAN, BLK_8X8, 0);

  821.         }

  822.         break;

  823.     default:

  824.         if (mb_type <= B_SYM_16X16) {

  825.             av_log(h->s.avctx, AV_LOG_ERROR, "Invalid mb_type %d in B frame\n", mb_type);

  826.             return AVERROR_INVALIDDATA;

  827.         }

  828.         av_assert2(mb_type < B_8X8);

  829.         flags = ff_cavs_partition_flags[mb_type];

  830.         if(mb_type & 1) { /* 16x8 macroblock types */

  831.             if(flags & FWD0)

  832.                 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP,  BLK_16X8, 1);

  833.             if(flags & SYM0)

  834.                 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X8);

  835.             if(flags & FWD1)

  836.                 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1);

  837.             if(flags & SYM1)

  838.                 mv_pred_sym(h, &h->mv[MV_FWD_X2], BLK_16X8);

  839.             if(flags & BWD0)

  840.                 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_TOP,  BLK_16X8, 0);

  841.             if(flags & BWD1)

  842.                 ff_cavs_mv(h, MV_BWD_X2, MV_BWD_A1, MV_PRED_LEFT, BLK_16X8, 0);

  843.         } else {          /* 8x16 macroblock types */

  844.             if(flags & FWD0)

  845.                 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1);

  846.             if(flags & SYM0)

  847.                 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_8X16);

  848.             if(flags & FWD1)

  849.                 ff_cavs_mv(h,MV_FWD_X1,MV_FWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,1);

  850.             if(flags & SYM1)

  851.                 mv_pred_sym(h, &h->mv[MV_FWD_X1], BLK_8X16);

  852.             if(flags & BWD0)

  853.                 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_B3, MV_PRED_LEFT, BLK_8X16, 0);

  854.             if(flags & BWD1)

  855.                 ff_cavs_mv(h,MV_BWD_X1,MV_BWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,0);

  856.         }

  857.     }

  858.     ff_cavs_inter(h, mb_type);

  859.     set_intra_mode_default(h);

  860.     if(mb_type != B_SKIP)

  861.         decode_residual_inter(h);

  862.     ff_cavs_filter(h,mb_type);

  863. 

  864.     return 0;

  865. }

  866. 

  867. /*****************************************************************************

  868.  *

  869.  * slice level

  870.  *

  871.  ****************************************************************************/

  872. 

  873. static inline int decode_slice_header(AVSContext *h, GetBitContext *gb) {

  874.     if(h->stc > 0xAF)

  875.         av_log(h->s.avctx, AV_LOG_ERROR, "unexpected start code 0x%02x\n", h->stc);

  876. 

  877.     if (h->stc >= h->mb_height)

  878.         return -1;

  879. 

  880.     h->mby = h->stc;

  881.     h->mbidx = h->mby*h->mb_width;

  882. 

  883.     /* mark top macroblocks as unavailable */

  884.     h->flags &= ~(B_AVAIL|C_AVAIL);

  885.     if((h->mby == 0) && (!h->qp_fixed)){

  886.         h->qp_fixed = get_bits1(gb);

  887.         h->qp = get_bits(gb,6);

  888.     }

  889.     /* inter frame or second slice can have weighting params */

  890.     if((h->pic_type != AV_PICTURE_TYPE_I) || (!h->pic_structure && h->mby >= h->mb_width/2))

  891.         if(get_bits1(gb)) { //slice_weighting_flag

  892.             av_log(h->s.avctx, AV_LOG_ERROR,

  893.                    "weighted prediction not yet supported\n");

  894.         }

  895.     return 0;

  896. }

  897. 

  898. static inline int check_for_slice(AVSContext *h) {

  899.     GetBitContext *gb = &h->s.gb;

  900.     int align;

  901. 

  902.     if(h->mbx)

  903.         return 0;

  904.     align = (-get_bits_count(gb)) & 7;

  905.     /* check for stuffing byte */

  906.     if(!align && (show_bits(gb,8) == 0x80))

  907.         align = 8;

  908.     if((show_bits_long(gb,24+align) & 0xFFFFFF) == 0x000001) {

  909.         skip_bits_long(gb,24+align);

  910.         h->stc = get_bits(gb,8);

  911.         if (h->stc >= h->mb_height)

  912.             return 0;

  913.         decode_slice_header(h,gb);

  914.         return 1;

  915.     }

  916.     return 0;

  917. }

  918. 

  919. /*****************************************************************************

  920.  *

  921.  * frame level

  922.  *

  923.  ****************************************************************************/

  924. 

  925. static int decode_pic(AVSContext *h) {

  926.     MpegEncContext *s = &h->s;

  927.     int skip_count = -1;

  928.     enum cavs_mb mb_type;

  929. 

  930.     if (!s->context_initialized) {

  931.         if (ff_MPV_common_init(s) < 0)

  932.             return -1;

  933.         ff_init_scantable_permutation(s->dsp.idct_permutation,

  934.                                       h->cdsp.idct_perm);

  935.         ff_init_scantable(s->dsp.idct_permutation,&h->scantable,ff_zigzag_direct);

  936.     }

  937.     skip_bits(&s->gb,16);//bbv_dwlay

  938.     if(h->stc == PIC_PB_START_CODE) {

  939.         h->pic_type = get_bits(&s->gb,2) + AV_PICTURE_TYPE_I;

  940.         if(h->pic_type > AV_PICTURE_TYPE_B) {

  941.             av_log(s->avctx, AV_LOG_ERROR, "illegal picture type\n");

  942.             return -1;

  943.         }

  944.         /* make sure we have the reference frames we need */

  945.         if(!h->DPB[0].f.data[0] ||

  946.           (!h->DPB[1].f.data[0] && h->pic_type == AV_PICTURE_TYPE_B))

  947.             return -1;

  948.     } else {

  949.         h->pic_type = AV_PICTURE_TYPE_I;

  950.         if(get_bits1(&s->gb))

  951.             skip_bits(&s->gb,24);//time_code

  952.         /* old sample clips were all progressive and no low_delay,

  953.            bump stream revision if detected otherwise */

  954.         if (s->low_delay || !(show_bits(&s->gb,9) & 1))

  955.             h->stream_revision = 1;

  956.         /* similarly test top_field_first and repeat_first_field */

  957.         else if(show_bits(&s->gb,11) & 3)

  958.             h->stream_revision = 1;

  959.         if(h->stream_revision > 0)

  960.             skip_bits(&s->gb,1); //marker_bit

  961.     }

  962.     /* release last B frame */

  963.     if(h->picture.f.data[0])

  964.         s->avctx->release_buffer(s->avctx, &h->picture.f);

  965. 

  966.     ff_get_buffer(s->avctx, &h->picture.f);

  967.     ff_cavs_init_pic(h);

  968.     h->picture.poc = get_bits(&s->gb,8)*2;

  969. 

  970.     /* get temporal distances and MV scaling factors */

  971.     if(h->pic_type != AV_PICTURE_TYPE_B) {

  972.         h->dist[0] = (h->picture.poc - h->DPB[0].poc  + 512) % 512;

  973.     } else {

  974.         h->dist[0] = (h->DPB[0].poc  - h->picture.poc + 512) % 512;

  975.     }

  976.     h->dist[1] = (h->picture.poc - h->DPB[1].poc  + 512) % 512;

  977.     h->scale_den[0] = h->dist[0] ? 512/h->dist[0] : 0;

  978.     h->scale_den[1] = h->dist[1] ? 512/h->dist[1] : 0;

  979.     if(h->pic_type == AV_PICTURE_TYPE_B) {

  980.         h->sym_factor = h->dist[0]*h->scale_den[1];

  981.     } else {

  982.         h->direct_den[0] = h->dist[0] ? 16384/h->dist[0] : 0;

  983.         h->direct_den[1] = h->dist[1] ? 16384/h->dist[1] : 0;

  984.     }

  985. 

  986.     if(s->low_delay)

  987.         get_ue_golomb(&s->gb); //bbv_check_times

  988.     h->progressive             = get_bits1(&s->gb);

  989.     h->pic_structure = 1;

  990.     if(!h->progressive)

  991.         h->pic_structure = get_bits1(&s->gb);

  992.     if(!h->pic_structure && h->stc == PIC_PB_START_CODE)

  993.         skip_bits1(&s->gb);     //advanced_pred_mode_disable

  994.     skip_bits1(&s->gb);        //top_field_first

  995.     skip_bits1(&s->gb);        //repeat_first_field

  996.     h->qp_fixed                = get_bits1(&s->gb);

  997.     h->qp                      = get_bits(&s->gb,6);

  998.     if(h->pic_type == AV_PICTURE_TYPE_I) {

  999.         if(!h->progressive && !h->pic_structure)

  1000.             skip_bits1(&s->gb);//what is this?

  1001.         skip_bits(&s->gb,4);   //reserved bits

  1002.     } else {

  1003.         if(!(h->pic_type == AV_PICTURE_TYPE_B && h->pic_structure == 1))

  1004.             h->ref_flag        = get_bits1(&s->gb);

  1005.         skip_bits(&s->gb,4);   //reserved bits

  1006.         h->skip_mode_flag      = get_bits1(&s->gb);

  1007.     }

  1008.     h->loop_filter_disable     = get_bits1(&s->gb);

  1009.     if(!h->loop_filter_disable && get_bits1(&s->gb)) {

  1010.         h->alpha_offset        = get_se_golomb(&s->gb);

  1011.         h->beta_offset         = get_se_golomb(&s->gb);

  1012.     } else {

  1013.         h->alpha_offset = h->beta_offset  = 0;

  1014.     }

  1015.     if(h->pic_type == AV_PICTURE_TYPE_I) {

  1016.         do {

  1017.             check_for_slice(h);

  1018.             decode_mb_i(h, 0);

  1019.         } while(ff_cavs_next_mb(h));

  1020.     } else if(h->pic_type == AV_PICTURE_TYPE_P) {

  1021.         do {

  1022.             if(check_for_slice(h))

  1023.                 skip_count = -1;

  1024.             if(h->skip_mode_flag && (skip_count < 0))

  1025.                 skip_count = get_ue_golomb(&s->gb);

  1026.             if(h->skip_mode_flag && skip_count--) {

  1027.                 decode_mb_p(h,P_SKIP);

  1028.             } else {

  1029.                 mb_type = get_ue_golomb(&s->gb) + P_SKIP + h->skip_mode_flag;

  1030.                 if(mb_type > P_8X8)

  1031.                     decode_mb_i(h, mb_type - P_8X8 - 1);

  1032.                 else

  1033.                     decode_mb_p(h,mb_type);

  1034.             }

  1035.         } while(ff_cavs_next_mb(h));

  1036.     } else { /* AV_PICTURE_TYPE_B */

  1037.         do {

  1038.             if(check_for_slice(h))

  1039.                 skip_count = -1;

  1040.             if(h->skip_mode_flag && (skip_count < 0))

  1041.                 skip_count = get_ue_golomb(&s->gb);

  1042.             if(h->skip_mode_flag && skip_count--) {

  1043.                 decode_mb_b(h,B_SKIP);

  1044.             } else {

  1045.                 mb_type = get_ue_golomb(&s->gb) + B_SKIP + h->skip_mode_flag;

  1046.                 if(mb_type > B_8X8)

  1047.                     decode_mb_i(h, mb_type - B_8X8 - 1);

  1048.                 else

  1049.                     decode_mb_b(h,mb_type);

  1050.             }

  1051.         } while(ff_cavs_next_mb(h));

  1052.     }

  1053.     if(h->pic_type != AV_PICTURE_TYPE_B) {

  1054.         if(h->DPB[1].f.data[0])

  1055.             s->avctx->release_buffer(s->avctx, &h->DPB[1].f);

  1056.         h->DPB[1] = h->DPB[0];

  1057.         h->DPB[0] = h->picture;

  1058.         memset(&h->picture,0,sizeof(Picture));

  1059.     }

  1060.     return 0;

  1061. }

  1062. 

  1063. /*****************************************************************************

  1064.  *

  1065.  * headers and interface

  1066.  *

  1067.  ****************************************************************************/

  1068. 

  1069. static int decode_seq_header(AVSContext *h) {

  1070.     MpegEncContext *s = &h->s;

  1071.     int frame_rate_code;

  1072.     int width, height;

  1073. 

  1074.     h->profile =         get_bits(&s->gb,8);

  1075.     h->level =           get_bits(&s->gb,8);

  1076.     skip_bits1(&s->gb); //progressive sequence

  1077. 

  1078.     width  = get_bits(&s->gb, 14);

  1079.     height = get_bits(&s->gb, 14);

  1080.     if ((s->width || s->height) && (s->width != width || s->height != height)) {

  1081.         av_log_missing_feature(s, "Width/height changing in CAVS", 0);

  1082.         return AVERROR_PATCHWELCOME;

  1083.     }

  1084.     if (width <= 0 || height <= 0) {

  1085.         av_log(s, AV_LOG_ERROR, "Dimensions invalid\n");

  1086.         return AVERROR_INVALIDDATA;

  1087.     }

  1088.     s->width  = width;

  1089.     s->height = height;

  1090. 

  1091.     skip_bits(&s->gb,2); //chroma format

  1092.     skip_bits(&s->gb,3); //sample_precision

  1093.     h->aspect_ratio =    get_bits(&s->gb,4);

  1094.     frame_rate_code =    get_bits(&s->gb,4);

  1095.     skip_bits(&s->gb,18);//bit_rate_lower

  1096.     skip_bits1(&s->gb);  //marker_bit

  1097.     skip_bits(&s->gb,12);//bit_rate_upper

  1098.     s->low_delay =       get_bits1(&s->gb);

  1099.     h->mb_width  = (s->width  + 15) >> 4;

  1100.     h->mb_height = (s->height + 15) >> 4;

  1101.     h->s.avctx->time_base.den = ff_mpeg12_frame_rate_tab[frame_rate_code].num;

  1102.     h->s.avctx->time_base.num = ff_mpeg12_frame_rate_tab[frame_rate_code].den;

  1103.     h->s.avctx->width  = s->width;

  1104.     h->s.avctx->height = s->height;

  1105.     if(!h->top_qp)

  1106.         ff_cavs_init_top_lines(h);

  1107.     return 0;

  1108. }

  1109. 

  1110. static void cavs_flush(AVCodecContext * avctx) {

  1111.     AVSContext *h = avctx->priv_data;

  1112.     h->got_keyframe = 0;

  1113. }

  1114. 

  1115. static int cavs_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

  1116.                              AVPacket *avpkt) {

  1117.     const uint8_t *buf = avpkt->data;

  1118.     int buf_size = avpkt->size;

  1119.     AVSContext *h = avctx->priv_data;

  1120.     MpegEncContext *s = &h->s;

  1121.     int input_size;

  1122.     const uint8_t *buf_end;

  1123.     const uint8_t *buf_ptr;

  1124.     AVFrame *picture = data;

  1125.     uint32_t stc = -1;

  1126. 

  1127.     s->avctx = avctx;

  1128. 

  1129.     if (buf_size == 0) {

  1130.         if (!s->low_delay && h->DPB[0].f.data[0]) {

  1131.             *got_frame = 1;

  1132.             *picture = h->DPB[0].f;

  1133.             memset(&h->DPB[0], 0, sizeof(h->DPB[0]));

  1134.         }

  1135.         return 0;

  1136.     }

  1137. 

  1138.     buf_ptr = buf;

  1139.     buf_end = buf + buf_size;

  1140.     for(;;) {

  1141.         buf_ptr = avpriv_mpv_find_start_code(buf_ptr,buf_end, &stc);

  1142.         if((stc & 0xFFFFFE00) || buf_ptr == buf_end)

  1143.             return FFMAX(0, buf_ptr - buf - s->parse_context.last_index);

  1144.         input_size = (buf_end - buf_ptr)*8;

  1145.         switch(stc) {

  1146.         case CAVS_START_CODE:

  1147.             init_get_bits(&s->gb, buf_ptr, input_size);

  1148.             decode_seq_header(h);

  1149.             break;

  1150.         case PIC_I_START_CODE:

  1151.             if(!h->got_keyframe) {

  1152.                 if(h->DPB[0].f.data[0])

  1153.                     avctx->release_buffer(avctx, &h->DPB[0].f);

  1154.                 if(h->DPB[1].f.data[0])

  1155.                     avctx->release_buffer(avctx, &h->DPB[1].f);

  1156.                 h->got_keyframe = 1;

  1157.             }

  1158.         case PIC_PB_START_CODE:

  1159.             *got_frame = 0;

  1160.             if(!h->got_keyframe)

  1161.                 break;

  1162.             if(!h->top_qp)

  1163.                 break;

  1164.             init_get_bits(&s->gb, buf_ptr, input_size);

  1165.             h->stc = stc;

  1166.             if(decode_pic(h))

  1167.                 break;

  1168.             *got_frame = 1;

  1169.             if(h->pic_type != AV_PICTURE_TYPE_B) {

  1170.                 if(h->DPB[1].f.data[0]) {

  1171.                     *picture = h->DPB[1].f;

  1172.                 } else {

  1173.                     *got_frame = 0;

  1174.                 }

  1175.             } else

  1176.                 *picture = h->picture.f;

  1177.             break;

  1178.         case EXT_START_CODE:

  1179.             //mpeg_decode_extension(avctx,buf_ptr, input_size);

  1180.             break;

  1181.         case USER_START_CODE:

  1182.             //mpeg_decode_user_data(avctx,buf_ptr, input_size);

  1183.             break;

  1184.         default:

  1185.             if (stc <= SLICE_MAX_START_CODE) {

  1186.                 init_get_bits(&s->gb, buf_ptr, input_size);

  1187.                 decode_slice_header(h, &s->gb);

  1188.             }

  1189.             break;

  1190.         }

  1191.     }

  1192. }

  1193. 

  1194. AVCodec ff_cavs_decoder = {

  1195.     .name           = "cavs",

  1196.     .type           = AVMEDIA_TYPE_VIDEO,

  1197.     .id             = AV_CODEC_ID_CAVS,

  1198.     .priv_data_size = sizeof(AVSContext),

  1199.     .init           = ff_cavs_init,

  1200.     .close          = ff_cavs_end,

  1201.     .decode         = cavs_decode_frame,

  1202.     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_DELAY,

  1203.     .flush          = cavs_flush,

  1204.     .long_name      = NULL_IF_CONFIG_SMALL("Chinese AVS (Audio Video Standard) (AVS1-P2, JiZhun profile)"),

  1205. };