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mpegvideo_xvmc.c
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1 /*
2  * XVideo Motion Compensation
3  * Copyright (c) 2003 Ivan Kalvachev
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 #include <limits.h>
23 #include <X11/extensions/XvMC.h>
24 
25 #include "avcodec.h"
26 #include "dsputil.h"
27 #include "mpegvideo.h"
28 
29 #undef NDEBUG
30 #include <assert.h>
31 
32 #include "xvmc.h"
33 #include "xvmc_internal.h"
34 
35 /**
36  * Initialize the block field of the MpegEncContext pointer passed as
37  * parameter after making sure that the data is not corrupted.
38  * In order to implement something like direct rendering instead of decoding
39  * coefficients in s->blocks and then copying them, copy them directly
40  * into the data_blocks array provided by xvmc.
41  */
43 {
44  struct xvmc_pix_fmt *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
45  assert(render && render->xvmc_id == AV_XVMC_ID);
46 
47  s->block = (DCTELEM (*)[64])(render->data_blocks + render->next_free_data_block_num * 64);
48 }
49 
50 /**
51  * Fill individual block pointers, so there are no gaps in the data_block array
52  * in case not all blocks in the macroblock are coded.
53  */
55 {
56  int i, j = 0;
57  const int mb_block_count = 4 + (1 << s->chroma_format);
58 
59  cbp <<= 12-mb_block_count;
60  for (i = 0; i < mb_block_count; i++) {
61  if (cbp & (1 << 11))
62  s->pblocks[i] = &s->block[j++];
63  else
64  s->pblocks[i] = NULL;
65  cbp += cbp;
66  }
67 }
68 
69 /**
70  * Find and store the surfaces that are used as reference frames.
71  * This function should be called for every new field and/or frame.
72  * It should be safe to call the function a few times for the same field.
73  */
75 {
76  struct xvmc_pix_fmt *last, *next, *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
77  const int mb_block_count = 4 + (1 << s->chroma_format);
78 
79  assert(avctx);
80  if (!render || render->xvmc_id != AV_XVMC_ID ||
81  !render->data_blocks || !render->mv_blocks ||
82  (unsigned int)render->allocated_mv_blocks > INT_MAX/(64*6) ||
83  (unsigned int)render->allocated_data_blocks > INT_MAX/64 ||
84  !render->p_surface) {
85  av_log(avctx, AV_LOG_ERROR,
86  "Render token doesn't look as expected.\n");
87  return -1; // make sure that this is a render packet
88  }
89 
90  if (render->filled_mv_blocks_num) {
91  av_log(avctx, AV_LOG_ERROR,
92  "Rendering surface contains %i unprocessed blocks.\n",
93  render->filled_mv_blocks_num);
94  return -1;
95  }
96  if (render->allocated_mv_blocks < 1 ||
97  render->allocated_data_blocks < render->allocated_mv_blocks*mb_block_count ||
98  render->start_mv_blocks_num >= render->allocated_mv_blocks ||
99  render->next_free_data_block_num >
100  render->allocated_data_blocks -
101  mb_block_count*(render->allocated_mv_blocks-render->start_mv_blocks_num)) {
102  av_log(avctx, AV_LOG_ERROR,
103  "Rendering surface doesn't provide enough block structures to work with.\n");
104  return -1;
105  }
106 
108  render->flags = s->first_field ? 0 : XVMC_SECOND_FIELD;
109  render->p_future_surface = NULL;
110  render->p_past_surface = NULL;
111 
112  switch(s->pict_type) {
113  case AV_PICTURE_TYPE_I:
114  return 0; // no prediction from other frames
115  case AV_PICTURE_TYPE_B:
116  next = (struct xvmc_pix_fmt*)s->next_picture.f.data[2];
117  if (!next)
118  return -1;
119  if (next->xvmc_id != AV_XVMC_ID)
120  return -1;
121  render->p_future_surface = next->p_surface;
122  // no return here, going to set forward prediction
123  case AV_PICTURE_TYPE_P:
124  last = (struct xvmc_pix_fmt*)s->last_picture.f.data[2];
125  if (!last)
126  last = render; // predict second field from the first
127  if (last->xvmc_id != AV_XVMC_ID)
128  return -1;
129  render->p_past_surface = last->p_surface;
130  return 0;
131  }
132 
133 return -1;
134 }
135 
136 /**
137  * Complete frame/field rendering by passing any remaining blocks.
138  * Normally ff_draw_horiz_band() is called for each slice, however,
139  * some leftover blocks, for example from error_resilience(), may remain.
140  * It should be safe to call the function a few times for the same field.
141  */
143 {
144  struct xvmc_pix_fmt *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
145  assert(render);
146 
147  if (render->filled_mv_blocks_num > 0)
148  ff_draw_horiz_band(s, 0, 0);
149 }
150 
151 /**
152  * Synthesize the data needed by XvMC to render one macroblock of data.
153  * Fill all relevant fields, if necessary do IDCT.
154  */
156 {
157  XvMCMacroBlock *mv_block;
158  struct xvmc_pix_fmt *render;
159  int i, cbp, blocks_per_mb;
160 
161  const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
162 
163 
164  if (s->encoding) {
165  av_log(s->avctx, AV_LOG_ERROR, "XVMC doesn't support encoding!!!\n");
166  return;
167  }
168 
169  // from MPV_decode_mb(), update DC predictors for P macroblocks
170  if (!s->mb_intra) {
171  s->last_dc[0] =
172  s->last_dc[1] =
173  s->last_dc[2] = 128 << s->intra_dc_precision;
174  }
175 
176  // MC doesn't skip blocks
177  s->mb_skipped = 0;
178 
179 
180  // Do I need to export quant when I could not perform postprocessing?
181  // Anyway, it doesn't hurt.
182  s->current_picture.f.qscale_table[mb_xy] = s->qscale;
183 
184  // start of XVMC-specific code
185  render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
186  assert(render);
187  assert(render->xvmc_id == AV_XVMC_ID);
188  assert(render->mv_blocks);
189 
190  // take the next free macroblock
191  mv_block = &render->mv_blocks[render->start_mv_blocks_num +
192  render->filled_mv_blocks_num];
193 
194  mv_block->x = s->mb_x;
195  mv_block->y = s->mb_y;
196  mv_block->dct_type = s->interlaced_dct; // XVMC_DCT_TYPE_FRAME/FIELD;
197  if (s->mb_intra) {
198  mv_block->macroblock_type = XVMC_MB_TYPE_INTRA; // no MC, all done
199  } else {
200  mv_block->macroblock_type = XVMC_MB_TYPE_PATTERN;
201 
202  if (s->mv_dir & MV_DIR_FORWARD) {
203  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_FORWARD;
204  // PMV[n][dir][xy] = mv[dir][n][xy]
205  mv_block->PMV[0][0][0] = s->mv[0][0][0];
206  mv_block->PMV[0][0][1] = s->mv[0][0][1];
207  mv_block->PMV[1][0][0] = s->mv[0][1][0];
208  mv_block->PMV[1][0][1] = s->mv[0][1][1];
209  }
210  if (s->mv_dir & MV_DIR_BACKWARD) {
211  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_BACKWARD;
212  mv_block->PMV[0][1][0] = s->mv[1][0][0];
213  mv_block->PMV[0][1][1] = s->mv[1][0][1];
214  mv_block->PMV[1][1][0] = s->mv[1][1][0];
215  mv_block->PMV[1][1][1] = s->mv[1][1][1];
216  }
217 
218  switch(s->mv_type) {
219  case MV_TYPE_16X16:
220  mv_block->motion_type = XVMC_PREDICTION_FRAME;
221  break;
222  case MV_TYPE_16X8:
223  mv_block->motion_type = XVMC_PREDICTION_16x8;
224  break;
225  case MV_TYPE_FIELD:
226  mv_block->motion_type = XVMC_PREDICTION_FIELD;
227  if (s->picture_structure == PICT_FRAME) {
228  mv_block->PMV[0][0][1] <<= 1;
229  mv_block->PMV[1][0][1] <<= 1;
230  mv_block->PMV[0][1][1] <<= 1;
231  mv_block->PMV[1][1][1] <<= 1;
232  }
233  break;
234  case MV_TYPE_DMV:
235  mv_block->motion_type = XVMC_PREDICTION_DUAL_PRIME;
236  if (s->picture_structure == PICT_FRAME) {
237 
238  mv_block->PMV[0][0][0] = s->mv[0][0][0]; // top from top
239  mv_block->PMV[0][0][1] = s->mv[0][0][1] << 1;
240 
241  mv_block->PMV[0][1][0] = s->mv[0][0][0]; // bottom from bottom
242  mv_block->PMV[0][1][1] = s->mv[0][0][1] << 1;
243 
244  mv_block->PMV[1][0][0] = s->mv[0][2][0]; // dmv00, top from bottom
245  mv_block->PMV[1][0][1] = s->mv[0][2][1] << 1; // dmv01
246 
247  mv_block->PMV[1][1][0] = s->mv[0][3][0]; // dmv10, bottom from top
248  mv_block->PMV[1][1][1] = s->mv[0][3][1] << 1; // dmv11
249 
250  } else {
251  mv_block->PMV[0][1][0] = s->mv[0][2][0]; // dmv00
252  mv_block->PMV[0][1][1] = s->mv[0][2][1]; // dmv01
253  }
254  break;
255  default:
256  assert(0);
257  }
258 
259  mv_block->motion_vertical_field_select = 0;
260 
261  // set correct field references
262  if (s->mv_type == MV_TYPE_FIELD || s->mv_type == MV_TYPE_16X8) {
263  mv_block->motion_vertical_field_select |= s->field_select[0][0];
264  mv_block->motion_vertical_field_select |= s->field_select[1][0] << 1;
265  mv_block->motion_vertical_field_select |= s->field_select[0][1] << 2;
266  mv_block->motion_vertical_field_select |= s->field_select[1][1] << 3;
267  }
268  } // !intra
269  // time to handle data blocks
270  mv_block->index = render->next_free_data_block_num;
271 
272  blocks_per_mb = 6;
273  if (s->chroma_format >= 2) {
274  blocks_per_mb = 4 + (1 << s->chroma_format);
275  }
276 
277  // calculate cbp
278  cbp = 0;
279  for (i = 0; i < blocks_per_mb; i++) {
280  cbp += cbp;
281  if (s->block_last_index[i] >= 0)
282  cbp++;
283  }
284 
285  if (s->flags & CODEC_FLAG_GRAY) {
286  if (s->mb_intra) { // intra frames are always full chroma blocks
287  for (i = 4; i < blocks_per_mb; i++) {
288  memset(s->pblocks[i], 0, sizeof(*s->pblocks[i])); // so we need to clear them
289  if (!render->unsigned_intra)
290  *s->pblocks[i][0] = 1 << 10;
291  }
292  } else {
293  cbp &= 0xf << (blocks_per_mb - 4);
294  blocks_per_mb = 4; // luminance blocks only
295  }
296  }
297  mv_block->coded_block_pattern = cbp;
298  if (cbp == 0)
299  mv_block->macroblock_type &= ~XVMC_MB_TYPE_PATTERN;
300 
301  for (i = 0; i < blocks_per_mb; i++) {
302  if (s->block_last_index[i] >= 0) {
303  // I do not have unsigned_intra MOCO to test, hope it is OK.
304  if (s->mb_intra && (render->idct || !render->unsigned_intra))
305  *s->pblocks[i][0] -= 1 << 10;
306  if (!render->idct) {
307  s->dsp.idct(*s->pblocks[i]);
308  /* It is unclear if MC hardware requires pixel diff values to be
309  * in the range [-255;255]. TODO: Clipping if such hardware is
310  * ever found. As of now it would only be an unnecessary
311  * slowdown. */
312  }
313  // copy blocks only if the codec doesn't support pblocks reordering
314  if (s->avctx->xvmc_acceleration == 1) {
315  memcpy(&render->data_blocks[render->next_free_data_block_num*64],
316  s->pblocks[i], sizeof(*s->pblocks[i]));
317  }
318  render->next_free_data_block_num++;
319  }
320  }
321  render->filled_mv_blocks_num++;
322 
323  assert(render->filled_mv_blocks_num <= render->allocated_mv_blocks);
324  assert(render->next_free_data_block_num <= render->allocated_data_blocks);
325  /* The above conditions should not be able to fail as long as this function
326  * is used and the following 'if ()' automatically calls a callback to free
327  * blocks. */
328 
329 
330  if (render->filled_mv_blocks_num == render->allocated_mv_blocks)
331  ff_draw_horiz_band(s, 0, 0);
332 }