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vf_spp.c
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1 /*
2  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
3  * Copyright (c) 2013 Clément Bœsch <u pkh me>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (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
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20  */
21 
22 /**
23  * @file
24  * Simple post processing filter
25  *
26  * This implementation is based on an algorithm described in
27  * "Aria Nosratinia Embedded Post-Processing for
28  * Enhancement of Compressed Images (1999)"
29  *
30  * Originally written by Michael Niedermayer for the MPlayer project, and
31  * ported by Clément Bœsch for FFmpeg.
32  */
33 
34 #include "libavutil/avassert.h"
35 #include "libavutil/imgutils.h"
36 #include "libavutil/opt.h"
37 #include "libavutil/pixdesc.h"
38 #include "internal.h"
39 #include "vf_spp.h"
40 
41 enum mode {
45 };
46 
47 static const AVClass *child_class_next(const AVClass *prev)
48 {
49  return prev ? NULL : avcodec_dct_get_class();
50 }
51 
52 static void *child_next(void *obj, void *prev)
53 {
54  SPPContext *s = obj;
55  return prev ? NULL : s->dct;
56 }
57 
58 #define OFFSET(x) offsetof(SPPContext, x)
59 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
60 static const AVOption spp_options[] = {
61  { "quality", "set quality", OFFSET(log2_count), AV_OPT_TYPE_INT, {.i64 = 3}, 0, MAX_LEVEL, FLAGS },
62  { "qp", "force a constant quantizer parameter", OFFSET(qp), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 63, FLAGS },
63  { "mode", "set thresholding mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64 = MODE_HARD}, 0, NB_MODES - 1, FLAGS, "mode" },
64  { "hard", "hard thresholding", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_HARD}, INT_MIN, INT_MAX, FLAGS, "mode" },
65  { "soft", "soft thresholding", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_SOFT}, INT_MIN, INT_MAX, FLAGS, "mode" },
66  { "use_bframe_qp", "use B-frames' QP", OFFSET(use_bframe_qp), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, FLAGS },
67  { NULL }
68 };
69 
70 static const AVClass spp_class = {
71  .class_name = "spp",
72  .item_name = av_default_item_name,
73  .option = spp_options,
74  .version = LIBAVUTIL_VERSION_INT,
75  .category = AV_CLASS_CATEGORY_FILTER,
76  .child_class_next = child_class_next,
78 };
79 
80 // XXX: share between filters?
81 DECLARE_ALIGNED(8, static const uint8_t, ldither)[8][8] = {
82  { 0, 48, 12, 60, 3, 51, 15, 63 },
83  { 32, 16, 44, 28, 35, 19, 47, 31 },
84  { 8, 56, 4, 52, 11, 59, 7, 55 },
85  { 40, 24, 36, 20, 43, 27, 39, 23 },
86  { 2, 50, 14, 62, 1, 49, 13, 61 },
87  { 34, 18, 46, 30, 33, 17, 45, 29 },
88  { 10, 58, 6, 54, 9, 57, 5, 53 },
89  { 42, 26, 38, 22, 41, 25, 37, 21 },
90 };
91 
92 static const uint8_t offset[127][2] = {
93  {0,0},
94  {0,0}, {4,4}, // quality = 1
95  {0,0}, {2,2}, {6,4}, {4,6}, // quality = 2
96  {0,0}, {5,1}, {2,2}, {7,3}, {4,4}, {1,5}, {6,6}, {3,7}, // quality = 3
97 
98  {0,0}, {4,0}, {1,1}, {5,1}, {3,2}, {7,2}, {2,3}, {6,3}, // quality = 4
99  {0,4}, {4,4}, {1,5}, {5,5}, {3,6}, {7,6}, {2,7}, {6,7},
100 
101  {0,0}, {0,2}, {0,4}, {0,6}, {1,1}, {1,3}, {1,5}, {1,7}, // quality = 5
102  {2,0}, {2,2}, {2,4}, {2,6}, {3,1}, {3,3}, {3,5}, {3,7},
103  {4,0}, {4,2}, {4,4}, {4,6}, {5,1}, {5,3}, {5,5}, {5,7},
104  {6,0}, {6,2}, {6,4}, {6,6}, {7,1}, {7,3}, {7,5}, {7,7},
105 
106  {0,0}, {4,4}, {0,4}, {4,0}, {2,2}, {6,6}, {2,6}, {6,2}, // quality = 6
107  {0,2}, {4,6}, {0,6}, {4,2}, {2,0}, {6,4}, {2,4}, {6,0},
108  {1,1}, {5,5}, {1,5}, {5,1}, {3,3}, {7,7}, {3,7}, {7,3},
109  {1,3}, {5,7}, {1,7}, {5,3}, {3,1}, {7,5}, {3,5}, {7,1},
110  {0,1}, {4,5}, {0,5}, {4,1}, {2,3}, {6,7}, {2,7}, {6,3},
111  {0,3}, {4,7}, {0,7}, {4,3}, {2,1}, {6,5}, {2,5}, {6,1},
112  {1,0}, {5,4}, {1,4}, {5,0}, {3,2}, {7,6}, {3,6}, {7,2},
113  {1,2}, {5,6}, {1,6}, {5,2}, {3,0}, {7,4}, {3,4}, {7,0},
114 };
115 
116 static void hardthresh_c(int16_t dst[64], const int16_t src[64],
117  int qp, const uint8_t *permutation)
118 {
119  int i;
120  int bias = 0; // FIXME
121 
122  unsigned threshold1 = qp * ((1<<4) - bias) - 1;
123  unsigned threshold2 = threshold1 << 1;
124 
125  memset(dst, 0, 64 * sizeof(dst[0]));
126  dst[0] = (src[0] + 4) >> 3;
127 
128  for (i = 1; i < 64; i++) {
129  int level = src[i];
130  if (((unsigned)(level + threshold1)) > threshold2) {
131  const int j = permutation[i];
132  dst[j] = (level + 4) >> 3;
133  }
134  }
135 }
136 
137 static void softthresh_c(int16_t dst[64], const int16_t src[64],
138  int qp, const uint8_t *permutation)
139 {
140  int i;
141  int bias = 0; //FIXME
142 
143  unsigned threshold1 = qp * ((1<<4) - bias) - 1;
144  unsigned threshold2 = threshold1 << 1;
145 
146  memset(dst, 0, 64 * sizeof(dst[0]));
147  dst[0] = (src[0] + 4) >> 3;
148 
149  for (i = 1; i < 64; i++) {
150  int level = src[i];
151  if (((unsigned)(level + threshold1)) > threshold2) {
152  const int j = permutation[i];
153  if (level > 0) dst[j] = (level - threshold1 + 4) >> 3;
154  else dst[j] = (level + threshold1 + 4) >> 3;
155  }
156  }
157 }
158 
159 static void store_slice_c(uint8_t *dst, const int16_t *src,
160  int dst_linesize, int src_linesize,
161  int width, int height, int log2_scale,
162  const uint8_t dither[8][8])
163 {
164  int y, x;
165 
166 #define STORE(pos) do { \
167  temp = ((src[x + y*src_linesize + pos] << log2_scale) + d[pos]) >> 6; \
168  if (temp & 0x100) \
169  temp = ~(temp >> 31); \
170  dst[x + y*dst_linesize + pos] = temp; \
171 } while (0)
172 
173  for (y = 0; y < height; y++) {
174  const uint8_t *d = dither[y];
175  for (x = 0; x < width; x += 8) {
176  int temp;
177  STORE(0);
178  STORE(1);
179  STORE(2);
180  STORE(3);
181  STORE(4);
182  STORE(5);
183  STORE(6);
184  STORE(7);
185  }
186  }
187 }
188 
189 static inline void add_block(int16_t *dst, int linesize, const int16_t block[64])
190 {
191  int y;
192 
193  for (y = 0; y < 8; y++) {
194  *(uint32_t *)&dst[0 + y*linesize] += *(uint32_t *)&block[0 + y*8];
195  *(uint32_t *)&dst[2 + y*linesize] += *(uint32_t *)&block[2 + y*8];
196  *(uint32_t *)&dst[4 + y*linesize] += *(uint32_t *)&block[4 + y*8];
197  *(uint32_t *)&dst[6 + y*linesize] += *(uint32_t *)&block[6 + y*8];
198  }
199 }
200 
201 // XXX: export the function?
202 static inline int norm_qscale(int qscale, int type)
203 {
204  switch (type) {
205  case FF_QSCALE_TYPE_MPEG1: return qscale;
206  case FF_QSCALE_TYPE_MPEG2: return qscale >> 1;
207  case FF_QSCALE_TYPE_H264: return qscale >> 2;
208  case FF_QSCALE_TYPE_VP56: return (63 - qscale + 2) >> 2;
209  }
210  return qscale;
211 }
212 
213 static void filter(SPPContext *p, uint8_t *dst, uint8_t *src,
214  int dst_linesize, int src_linesize, int width, int height,
215  const uint8_t *qp_table, int qp_stride, int is_luma)
216 {
217  int x, y, i;
218  const int count = 1 << p->log2_count;
219  const int linesize = is_luma ? p->temp_linesize : FFALIGN(width+16, 16);
220  DECLARE_ALIGNED(16, uint64_t, block_align)[32];
221  int16_t *block = (int16_t *)block_align;
222  int16_t *block2 = (int16_t *)(block_align + 16);
223 
224  for (y = 0; y < height; y++) {
225  int index = 8 + 8*linesize + y*linesize;
226  memcpy(p->src + index, src + y*src_linesize, width);
227  for (x = 0; x < 8; x++) {
228  p->src[index - x - 1] = p->src[index + x ];
229  p->src[index + width + x ] = p->src[index + width - x - 1];
230  }
231  }
232  for (y = 0; y < 8; y++) {
233  memcpy(p->src + ( 7-y)*linesize, p->src + ( y+8)*linesize, linesize);
234  memcpy(p->src + (height+8+y)*linesize, p->src + (height-y+7)*linesize, linesize);
235  }
236 
237  for (y = 0; y < height + 8; y += 8) {
238  memset(p->temp + (8 + y) * linesize, 0, 8 * linesize * sizeof(*p->temp));
239  for (x = 0; x < width + 8; x += 8) {
240  int qp;
241 
242  if (p->qp) {
243  qp = p->qp;
244  } else{
245  const int qps = 3 + is_luma;
246  qp = qp_table[(FFMIN(x, width - 1) >> qps) + (FFMIN(y, height - 1) >> qps) * qp_stride];
247  qp = FFMAX(1, norm_qscale(qp, p->qscale_type));
248  }
249  for (i = 0; i < count; i++) {
250  const int x1 = x + offset[i + count - 1][0];
251  const int y1 = y + offset[i + count - 1][1];
252  const int index = x1 + y1*linesize;
253  p->pdsp.get_pixels(block, p->src + index, linesize);
254  p->dct->fdct(block);
255  p->requantize(block2, block, qp, p->dct->idct_permutation);
256  p->dct->idct(block2);
257  add_block(p->temp + index, linesize, block2);
258  }
259  }
260  if (y)
261  p->store_slice(dst + (y - 8) * dst_linesize, p->temp + 8 + y*linesize,
262  dst_linesize, linesize, width,
263  FFMIN(8, height + 8 - y), MAX_LEVEL - p->log2_count,
264  ldither);
265  }
266 }
267 
269 {
270  static const enum PixelFormat pix_fmts[] = {
277  };
279  return 0;
280 }
281 
282 static int config_input(AVFilterLink *inlink)
283 {
284  SPPContext *spp = inlink->dst->priv;
285  const int h = FFALIGN(inlink->h + 16, 16);
286  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
287 
288  spp->hsub = desc->log2_chroma_w;
289  spp->vsub = desc->log2_chroma_h;
290  spp->temp_linesize = FFALIGN(inlink->w + 16, 16);
291  spp->temp = av_malloc_array(spp->temp_linesize, h * sizeof(*spp->temp));
292  spp->src = av_malloc_array(spp->temp_linesize, h * sizeof(*spp->src));
293  if (!spp->use_bframe_qp) {
294  /* we are assuming here the qp blocks will not be smaller that 16x16 */
295  spp->non_b_qp_alloc_size = FF_CEIL_RSHIFT(inlink->w, 4) * FF_CEIL_RSHIFT(inlink->h, 4);
296  spp->non_b_qp_table = av_calloc(spp->non_b_qp_alloc_size, sizeof(*spp->non_b_qp_table));
297  if (!spp->non_b_qp_table)
298  return AVERROR(ENOMEM);
299  }
300  if (!spp->temp || !spp->src)
301  return AVERROR(ENOMEM);
302  return 0;
303 }
304 
305 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
306 {
307  AVFilterContext *ctx = inlink->dst;
308  SPPContext *spp = ctx->priv;
309  AVFilterLink *outlink = ctx->outputs[0];
310  AVFrame *out = in;
311  int qp_stride = 0;
312  const int8_t *qp_table = NULL;
313 
314  /* if we are not in a constant user quantizer mode and we don't want to use
315  * the quantizers from the B-frames (B-frames often have a higher QP), we
316  * need to save the qp table from the last non B-frame; this is what the
317  * following code block does */
318  if (!spp->qp) {
319  qp_table = av_frame_get_qp_table(in, &qp_stride, &spp->qscale_type);
320 
321  if (qp_table && !spp->use_bframe_qp && in->pict_type != AV_PICTURE_TYPE_B) {
322  int w, h;
323 
324  /* if the qp stride is not set, it means the QP are only defined on
325  * a line basis */
326  if (!qp_stride) {
327  w = FF_CEIL_RSHIFT(inlink->w, 4);
328  h = 1;
329  } else {
330  w = FF_CEIL_RSHIFT(qp_stride, 4);
331  h = FF_CEIL_RSHIFT(inlink->h, 4);
332  }
333  av_assert0(w * h <= spp->non_b_qp_alloc_size);
334  memcpy(spp->non_b_qp_table, qp_table, w * h);
335  }
336  }
337 
338  if (spp->log2_count && !ctx->is_disabled) {
339  if (!spp->use_bframe_qp && spp->non_b_qp_table)
340  qp_table = spp->non_b_qp_table;
341 
342  if (qp_table || spp->qp) {
343  const int cw = FF_CEIL_RSHIFT(inlink->w, spp->hsub);
344  const int ch = FF_CEIL_RSHIFT(inlink->h, spp->vsub);
345 
346  /* get a new frame if in-place is not possible or if the dimensions
347  * are not multiple of 8 */
348  if (!av_frame_is_writable(in) || (inlink->w & 7) || (inlink->h & 7)) {
349  const int aligned_w = FFALIGN(inlink->w, 8);
350  const int aligned_h = FFALIGN(inlink->h, 8);
351 
352  out = ff_get_video_buffer(outlink, aligned_w, aligned_h);
353  if (!out) {
354  av_frame_free(&in);
355  return AVERROR(ENOMEM);
356  }
357  av_frame_copy_props(out, in);
358  out->width = in->width;
359  out->height = in->height;
360  }
361 
362  filter(spp, out->data[0], in->data[0], out->linesize[0], in->linesize[0], inlink->w, inlink->h, qp_table, qp_stride, 1);
363  filter(spp, out->data[1], in->data[1], out->linesize[1], in->linesize[1], cw, ch, qp_table, qp_stride, 0);
364  filter(spp, out->data[2], in->data[2], out->linesize[2], in->linesize[2], cw, ch, qp_table, qp_stride, 0);
365  emms_c();
366  }
367  }
368 
369  if (in != out) {
370  if (in->data[3])
371  av_image_copy_plane(out->data[3], out->linesize[3],
372  in ->data[3], in ->linesize[3],
373  inlink->w, inlink->h);
374  av_frame_free(&in);
375  }
376  return ff_filter_frame(outlink, out);
377 }
378 
379 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
380  char *res, int res_len, int flags)
381 {
382  SPPContext *spp = ctx->priv;
383 
384  if (!strcmp(cmd, "level")) {
385  if (!strcmp(args, "max"))
386  spp->log2_count = MAX_LEVEL;
387  else
388  spp->log2_count = av_clip(strtol(args, NULL, 10), 0, MAX_LEVEL);
389  return 0;
390  }
391  return AVERROR(ENOSYS);
392 }
393 
395 {
396  SPPContext *spp = ctx->priv;
397  int ret;
398 
399  spp->avctx = avcodec_alloc_context3(NULL);
400  spp->dct = avcodec_dct_alloc();
401  if (!spp->avctx || !spp->dct)
402  return AVERROR(ENOMEM);
403  ff_pixblockdsp_init(&spp->pdsp, spp->avctx);
404 
405  if (opts) {
406  AVDictionaryEntry *e = NULL;
407 
408  while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
409  if ((ret = av_opt_set(spp->dct, e->key, e->value, 0)) < 0)
410  return ret;
411  }
412  av_dict_free(opts);
413  }
414 
415  avcodec_dct_init(spp->dct);
416  spp->store_slice = store_slice_c;
417  switch (spp->mode) {
418  case MODE_HARD: spp->requantize = hardthresh_c; break;
419  case MODE_SOFT: spp->requantize = softthresh_c; break;
420  }
421  if (ARCH_X86)
422  ff_spp_init_x86(spp);
423  return 0;
424 }
425 
426 static av_cold void uninit(AVFilterContext *ctx)
427 {
428  SPPContext *spp = ctx->priv;
429 
430  av_freep(&spp->temp);
431  av_freep(&spp->src);
432  if (spp->avctx) {
433  avcodec_close(spp->avctx);
434  av_freep(&spp->avctx);
435  }
436  av_freep(&spp->dct);
437  av_freep(&spp->non_b_qp_table);
438 }
439 
440 static const AVFilterPad spp_inputs[] = {
441  {
442  .name = "default",
443  .type = AVMEDIA_TYPE_VIDEO,
444  .config_props = config_input,
445  .filter_frame = filter_frame,
446  },
447  { NULL }
448 };
449 
450 static const AVFilterPad spp_outputs[] = {
451  {
452  .name = "default",
453  .type = AVMEDIA_TYPE_VIDEO,
454  },
455  { NULL }
456 };
457 
459  .name = "spp",
460  .description = NULL_IF_CONFIG_SMALL("Apply a simple post processing filter."),
461  .priv_size = sizeof(SPPContext),
462  .init_dict = init_dict,
463  .uninit = uninit,
465  .inputs = spp_inputs,
466  .outputs = spp_outputs,
468  .priv_class = &spp_class,
470 };