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mpegvideo_bfin.c
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1 /*
2  * BlackFin MPEGVIDEO OPTIMIZATIONS
3  *
4  * Copyright (C) 2007 Marc Hoffman <mmh@pleasantst.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/attributes.h"
24 #include "libavcodec/avcodec.h"
25 #include "libavcodec/mpegvideo.h"
26 #include "dsputil_bfin.h"
27 
29  int16_t *block, int n,
30  int qscale, int *overflow)
31 {
32  int last_non_zero, q, start_i;
33  const short *qmat;
34  short *bias;
35  const uint8_t *scantable= s->intra_scantable.scantable;
36  short dc;
37  int max=0;
38 
39  PROF("fdct",0);
40  s->dsp.fdct(block);
41  EPROF();
42 
43  PROF("denoise",1);
44  if(s->dct_error_sum)
45  s->denoise_dct(s, block);
46  EPROF();
47 
48  PROF("quant-init",2);
49  if (s->mb_intra) {
50  if (!s->h263_aic) {
51  if (n < 4)
52  q = s->y_dc_scale;
53  else
54  q = s->c_dc_scale;
55  q = q << 3;
56  } else
57  /* For AIC we skip quant/dequant of INTRADC */
58  q = 1 << 3;
59 
60  /* note: block[0] is assumed to be positive */
61  dc = block[0] = (block[0] + (q >> 1)) / q;
62  start_i = 1;
63  last_non_zero = 0;
64  if(n<4){
65  bias = s->q_intra_matrix16[qscale][1];
66  qmat = s->q_intra_matrix16[qscale][0];
67  }else{
68  bias = s->q_chroma_intra_matrix16[qscale][1];
69  qmat = s->q_chroma_intra_matrix16[qscale][0];
70  }
71 
72  } else {
73  start_i = 0;
74  last_non_zero = -1;
75  bias = s->q_inter_matrix16[qscale][1];
76  qmat = s->q_inter_matrix16[qscale][0];
77 
78  }
79  EPROF();
80 
81  PROF("quantize",4);
82 
83  /* for(i=start_i; i<64; i++) { */
84  /* sign = (block[i]>>15)|1; */
85  /* level = ((abs(block[i])+bias[0])*qmat[i])>>16; */
86  /* if (level < 0) level = 0; */
87  /* max |= level; */
88  /* level = level * sign; */
89  /* block[i] = level; */
90  /* } */
91 
92  __asm__ volatile
93  ("i2=%1;\n\t"
94  "r1=[%1++]; \n\t"
95  "r0=r1>>>15 (v); \n\t"
96  "lsetup (0f,1f) lc0=%3; \n\t"
97  "0: r0=r0|%4; \n\t"
98  " r1=abs r1 (v) || r2=[%2++];\n\t"
99  " r1=r1+|+%5; \n\t"
100  " r1=max(r1,%6) (v); \n\t"
101  " r1.h=(a1 =r1.h*r2.h), r1.l=(a0 =r1.l*r2.l) (tfu); \n\t"
102  " %0=%0|r1; \n\t"
103  " r0.h=(a1 =r1.h*r0.h), r0.l=(a0 =r1.l*r0.l) (is) || r1=[%1++];\n\t"
104  "1: r0=r1>>>15 (v) || [i2++]=r0;\n\t"
105  "r1=%0>>16; \n\t"
106  "%0=%0|r1; \n\t"
107  "%0.h=0; \n\t"
108  : "=&d" (max)
109  : "b" (block), "b" (qmat), "a" (32), "d" (0x00010001), "d" (bias[0]*0x10001), "d" (0)
110  : "R0","R1","R2", "I2");
111  if (start_i == 1) block[0] = dc;
112 
113  EPROF();
114 
115 
116  PROF("zzscan",5);
117 
118  __asm__ volatile
119  ("r0=b[%1--] (x); \n\t"
120  "lsetup (0f,1f) lc0=%3; \n\t" /* for(i=63; i>=start_i; i--) { */
121  "0: p0=r0; \n\t" /* j = scantable[i]; */
122  " p0=%2+(p0<<1); \n\t" /* if (block[j]) { */
123  " r0=w[p0]; \n\t" /* last_non_zero = i; */
124  " cc=r0==0; \n\t" /* break; */
125  " if !cc jump 2f; \n\t" /* } */
126  "1: r0=b[%1--] (x); \n\t" /* } */
127  " %0=%4; \n\t"
128  " jump 3f; \n\t"
129  "2: %0=lc0; \n\t"
130  "3:\n\t"
131 
132  : "=d" (last_non_zero)
133  : "a" (scantable+63), "a" (block), "a" (63), "d" (last_non_zero)
134  : "P0","R0");
135 
136  EPROF();
137 
138  *overflow= s->max_qcoeff < max; //overflow might have happened
139 
140  bfprof();
141 
142  /* we need this permutation so that we correct the IDCT, we only permute the !=0 elements */
144  ff_block_permute(block, s->dsp.idct_permutation, scantable, last_non_zero);
145 
146  return last_non_zero;
147 }
148 
150 {
151 /* s->dct_quantize= dct_quantize_bfin; */
152 }