FFmpeg
ffv1dec_template.c
Go to the documentation of this file.
1 /*
2  * FFV1 decoder template
3  *
4  * Copyright (c) 2003-2016 Michael Niedermayer <michaelni@gmx.at>
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 "ffv1_template.c"
24 
26  TYPE *sample[2],
27  int plane_index, int bits)
28 {
29  PlaneContext *const p = &s->plane[plane_index];
30  RangeCoder *const c = &s->c;
31  int x;
32  int run_count = 0;
33  int run_mode = 0;
34  int run_index = s->run_index;
35 
36  if (is_input_end(s))
37  return AVERROR_INVALIDDATA;
38 
39  if (s->slice_coding_mode == 1) {
40  int i;
41  for (x = 0; x < w; x++) {
42  int v = 0;
43  for (i=0; i<bits; i++) {
44  uint8_t state = 128;
45  v += v + get_rac(c, &state);
46  }
47  sample[1][x] = v;
48  }
49  return 0;
50  }
51 
52  for (x = 0; x < w; x++) {
53  int diff, context, sign;
54 
55  if (!(x & 1023)) {
56  if (is_input_end(s))
57  return AVERROR_INVALIDDATA;
58  }
59 
60  context = RENAME(get_context)(p, sample[1] + x, sample[0] + x, sample[1] + x);
61  if (context < 0) {
62  context = -context;
63  sign = 1;
64  } else
65  sign = 0;
66 
67  av_assert2(context < p->context_count);
68 
69  if (s->ac != AC_GOLOMB_RICE) {
71  } else {
72  if (context == 0 && run_mode == 0)
73  run_mode = 1;
74 
75  if (run_mode) {
76  if (run_count == 0 && run_mode == 1) {
77  if (get_bits1(&s->gb)) {
78  run_count = 1 << ff_log2_run[run_index];
79  if (x + run_count <= w)
80  run_index++;
81  } else {
83  run_count = get_bits(&s->gb, ff_log2_run[run_index]);
84  else
85  run_count = 0;
86  if (run_index)
87  run_index--;
88  run_mode = 2;
89  }
90  }
91  if (sample[1][x - 1] == sample[0][x - 1]) {
92  while (run_count > 1 && w-x > 1) {
93  sample[1][x] = sample[0][x];
94  x++;
95  run_count--;
96  }
97  } else {
98  while (run_count > 1 && w-x > 1) {
99  sample[1][x] = RENAME(predict)(sample[1] + x, sample[0] + x);
100  x++;
101  run_count--;
102  }
103  }
104  run_count--;
105  if (run_count < 0) {
106  run_mode = 0;
107  run_count = 0;
108  diff = get_vlc_symbol(&s->gb, &p->vlc_state[context],
109  bits);
110  if (diff >= 0)
111  diff++;
112  } else
113  diff = 0;
114  } else
115  diff = get_vlc_symbol(&s->gb, &p->vlc_state[context], bits);
116 
117  ff_dlog(s->avctx, "count:%d index:%d, mode:%d, x:%d pos:%d\n",
118  run_count, run_index, run_mode, x, get_bits_count(&s->gb));
119  }
120 
121  if (sign)
122  diff = -(unsigned)diff;
123 
124  sample[1][x] = av_mod_uintp2(RENAME(predict)(sample[1] + x, sample[0] + x) + (SUINT)diff, bits);
125  }
126  s->run_index = run_index;
127  return 0;
128 }
129 
130 static int RENAME(decode_rgb_frame)(FFV1Context *s, uint8_t *src[4], int w, int h, int stride[4])
131 {
132  int x, y, p;
133  TYPE *sample[4][2];
134  int lbd = s->avctx->bits_per_raw_sample <= 8;
135  int bits = s->avctx->bits_per_raw_sample > 0 ? s->avctx->bits_per_raw_sample : 8;
136  int offset = 1 << bits;
137  int transparency = s->transparency;
138 
139  for (x = 0; x < 4; x++) {
140  sample[x][0] = RENAME(s->sample_buffer) + x * 2 * (w + 6) + 3;
141  sample[x][1] = RENAME(s->sample_buffer) + (x * 2 + 1) * (w + 6) + 3;
142  }
143 
144  s->run_index = 0;
145 
146  memset(RENAME(s->sample_buffer), 0, 8 * (w + 6) * sizeof(*RENAME(s->sample_buffer)));
147 
148  for (y = 0; y < h; y++) {
149  for (p = 0; p < 3 + transparency; p++) {
150  int ret;
151  TYPE *temp = sample[p][0]; // FIXME: try a normal buffer
152 
153  sample[p][0] = sample[p][1];
154  sample[p][1] = temp;
155 
156  sample[p][1][-1]= sample[p][0][0 ];
157  sample[p][0][ w]= sample[p][0][w-1];
158  if (lbd && s->slice_coding_mode == 0)
159  ret = RENAME(decode_line)(s, w, sample[p], (p + 1)/2, 9);
160  else
161  ret = RENAME(decode_line)(s, w, sample[p], (p + 1)/2, bits + (s->slice_coding_mode != 1));
162  if (ret < 0)
163  return ret;
164  }
165  for (x = 0; x < w; x++) {
166  int g = sample[0][1][x];
167  int b = sample[1][1][x];
168  int r = sample[2][1][x];
169  int a = sample[3][1][x];
170 
171  if (s->slice_coding_mode != 1) {
172  b -= offset;
173  r -= offset;
174  g -= (b * s->slice_rct_by_coef + r * s->slice_rct_ry_coef) >> 2;
175  b += g;
176  r += g;
177  }
178 
179  if (lbd)
180  *((uint32_t*)(src[0] + x*4 + stride[0]*y)) = b + ((unsigned)g<<8) + ((unsigned)r<<16) + ((unsigned)a<<24);
181  else if (sizeof(TYPE) == 4 || transparency) {
182  *((uint16_t*)(src[0] + x*2 + stride[0]*y)) = g;
183  *((uint16_t*)(src[1] + x*2 + stride[1]*y)) = b;
184  *((uint16_t*)(src[2] + x*2 + stride[2]*y)) = r;
185  if (transparency)
186  *((uint16_t*)(src[3] + x*2 + stride[3]*y)) = a;
187  } else {
188  *((uint16_t*)(src[0] + x*2 + stride[0]*y)) = b;
189  *((uint16_t*)(src[1] + x*2 + stride[1]*y)) = g;
190  *((uint16_t*)(src[2] + x*2 + stride[2]*y)) = r;
191  }
192  }
193  }
194  return 0;
195 }
r
const char * r
Definition: vf_curves.c:126
is_input_end
static int is_input_end(FFV1Context *s)
Definition: ffv1dec.c:97
FFV1Context::context_count
int context_count[MAX_QUANT_TABLES]
Definition: ffv1.h:101
get_bits_count
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
av_mod_uintp2
#define av_mod_uintp2
Definition: common.h:122
w
uint8_t w
Definition: llviddspenc.c:38
b
#define b
Definition: input.c:41
PlaneContext::state
uint8_t(* state)[CONTEXT_SIZE]
Definition: ffv1.h:66
decode_line
static av_always_inline int RENAME() decode_line(FFV1Context *s, int w, TYPE *sample[2], int plane_index, int bits)
Definition: ffv1dec_template.c:25
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
get_symbol_inline
static av_flatten int get_symbol_inline(RangeCoder *c, uint8_t *state, int is_signed)
Definition: ffv1dec.c:43
s
#define s(width, name)
Definition: cbs_vp9.c:256
g
const char * g
Definition: vf_curves.c:127
bits
uint8_t bits
Definition: vp3data.h:128
ffv1_template.c
get_vlc_symbol
static int get_vlc_symbol(GetBitContext *gb, VlcState *const state, int bits)
Definition: ffv1dec.c:72
state
static struct @344 state
context
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your context
Definition: writing_filters.txt:91
TYPE
#define TYPE
Definition: ffv1dec.c:116
PlaneContext::vlc_state
VlcState * vlc_state
Definition: ffv1.h:67
AC_GOLOMB_RICE
#define AC_GOLOMB_RICE
Definition: ffv1.h:50
get_bits1
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
PlaneContext
Definition: ffv1.h:62
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:28
sample
#define sample
Definition: flacdsp_template.c:44
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
av_assert2
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
predict
static av_always_inline void predict(PredictorState *ps, float *coef, int output_enable)
Definition: aacdec.c:176
av_always_inline
#define av_always_inline
Definition: attributes.h:49
SUINT
#define SUINT
Definition: dct32_template.c:30
get_rac
static int get_rac(RangeCoder *c, uint8_t *const state)
Definition: rangecoder.h:127
stride
#define stride
Definition: h264pred_template.c:537
ret
ret
Definition: filter_design.txt:187
decode_rgb_frame
static int RENAME() decode_rgb_frame(FFV1Context *s, uint8_t *src[4], int w, int h, int stride[4])
Definition: ffv1dec_template.c:130
temp
else temp
Definition: vf_mcdeint.c:248
FFV1Context
Definition: ffv1.h:73
diff
static av_always_inline int diff(const uint32_t a, const uint32_t b)
Definition: vf_palettegen.c:139
FFV1Context::transparency
int transparency
Definition: ffv1.h:86
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
ff_log2_run
const uint8_t ff_log2_run[41]
Definition: mathtables.c:116
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
h
h
Definition: vp9dsp_template.c:2038
RangeCoder
Definition: mss3.c:62
FFV1Context::run_index
int run_index
Definition: ffv1.h:104
RENAME
#define RENAME(name)
Definition: ffv1dec.c:117