FFmpeg
 All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
mpegvideo_xvmc.c
Go to the documentation of this file.
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 "mpegvideo.h"
27 
28 #undef NDEBUG
29 #include <assert.h>
30 
31 #include "xvmc.h"
32 #include "xvmc_internal.h"
33 
34 /**
35  * Initialize the block field of the MpegEncContext pointer passed as
36  * parameter after making sure that the data is not corrupted.
37  * In order to implement something like direct rendering instead of decoding
38  * coefficients in s->blocks and then copying them, copy them directly
39  * into the data_blocks array provided by xvmc.
40  */
42 {
43  struct xvmc_pix_fmt *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
44  assert(render && render->xvmc_id == AV_XVMC_ID);
45 
46  s->block = (int16_t (*)[64])(render->data_blocks + render->next_free_data_block_num * 64);
47 }
48 
49 /**
50  * Fill individual block pointers, so there are no gaps in the data_block array
51  * in case not all blocks in the macroblock are coded.
52  */
54 {
55  int i, j = 0;
56  const int mb_block_count = 4 + (1 << s->chroma_format);
57 
58  cbp <<= 12-mb_block_count;
59  for (i = 0; i < mb_block_count; i++) {
60  if (cbp & (1 << 11))
61  s->pblocks[i] = &s->block[j++];
62  else
63  s->pblocks[i] = NULL;
64  cbp += cbp;
65  }
66 }
67 
68 /**
69  * Find and store the surfaces that are used as reference frames.
70  * This function should be called for every new field and/or frame.
71  * It should be safe to call the function a few times for the same field.
72  */
74 {
75  struct xvmc_pix_fmt *last, *next, *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
76  const int mb_block_count = 4 + (1 << s->chroma_format);
77 
78  assert(avctx);
79  if (!render || render->xvmc_id != AV_XVMC_ID ||
80  !render->data_blocks || !render->mv_blocks ||
81  (unsigned int)render->allocated_mv_blocks > INT_MAX/(64*6) ||
82  (unsigned int)render->allocated_data_blocks > INT_MAX/64 ||
83  !render->p_surface) {
84  av_log(avctx, AV_LOG_ERROR,
85  "Render token doesn't look as expected.\n");
86  return -1; // make sure that this is a render packet
87  }
88 
89  if (render->filled_mv_blocks_num) {
90  av_log(avctx, AV_LOG_ERROR,
91  "Rendering surface contains %i unprocessed blocks.\n",
92  render->filled_mv_blocks_num);
93  return -1;
94  }
95  if (render->allocated_mv_blocks < 1 ||
96  render->allocated_data_blocks < render->allocated_mv_blocks*mb_block_count ||
97  render->start_mv_blocks_num >= render->allocated_mv_blocks ||
98  render->next_free_data_block_num >
99  render->allocated_data_blocks -
100  mb_block_count*(render->allocated_mv_blocks-render->start_mv_blocks_num)) {
101  av_log(avctx, AV_LOG_ERROR,
102  "Rendering surface doesn't provide enough block structures to work with.\n");
103  return -1;
104  }
105 
107  render->flags = s->first_field ? 0 : XVMC_SECOND_FIELD;
108  render->p_future_surface = NULL;
109  render->p_past_surface = NULL;
110 
111  switch(s->pict_type) {
112  case AV_PICTURE_TYPE_I:
113  return 0; // no prediction from other frames
114  case AV_PICTURE_TYPE_B:
115  next = (struct xvmc_pix_fmt*)s->next_picture.f.data[2];
116  if (!next)
117  return -1;
118  if (next->xvmc_id != AV_XVMC_ID)
119  return -1;
120  render->p_future_surface = next->p_surface;
121  // no return here, going to set forward prediction
122  case AV_PICTURE_TYPE_P:
123  last = (struct xvmc_pix_fmt*)s->last_picture.f.data[2];
124  if (!last)
125  last = render; // predict second field from the first
126  if (last->xvmc_id != AV_XVMC_ID)
127  return -1;
128  render->p_past_surface = last->p_surface;
129  return 0;
130  }
131 
132 return -1;
133 }
134 
135 /**
136  * Complete frame/field rendering by passing any remaining blocks.
137  * Normally ff_draw_horiz_band() is called for each slice, however,
138  * some leftover blocks, for example from error_resilience(), may remain.
139  * It should be safe to call the function a few times for the same field.
140  */
142 {
143  struct xvmc_pix_fmt *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
144  assert(render);
145 
146  if (render->filled_mv_blocks_num > 0)
147  ff_mpeg_draw_horiz_band(s, 0, 0);
148 }
149 
150 /**
151  * Synthesize the data needed by XvMC to render one macroblock of data.
152  * Fill all relevant fields, if necessary do IDCT.
153  */
155 {
156  XvMCMacroBlock *mv_block;
157  struct xvmc_pix_fmt *render;
158  int i, cbp, blocks_per_mb;
159 
160  const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
161 
162 
163  if (s->encoding) {
164  av_log(s->avctx, AV_LOG_ERROR, "XVMC doesn't support encoding!!!\n");
165  return;
166  }
167 
168  // from MPV_decode_mb(), update DC predictors for P macroblocks
169  if (!s->mb_intra) {
170  s->last_dc[0] =
171  s->last_dc[1] =
172  s->last_dc[2] = 128 << s->intra_dc_precision;
173  }
174 
175  // MC doesn't skip blocks
176  s->mb_skipped = 0;
177 
178 
179  // Do I need to export quant when I could not perform postprocessing?
180  // Anyway, it doesn't hurt.
181  s->current_picture.f.qscale_table[mb_xy] = s->qscale;
182 
183  // start of XVMC-specific code
184  render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
185  assert(render);
186  assert(render->xvmc_id == AV_XVMC_ID);
187  assert(render->mv_blocks);
188 
189  // take the next free macroblock
190  mv_block = &render->mv_blocks[render->start_mv_blocks_num +
191  render->filled_mv_blocks_num];
192 
193  mv_block->x = s->mb_x;
194  mv_block->y = s->mb_y;
195  mv_block->dct_type = s->interlaced_dct; // XVMC_DCT_TYPE_FRAME/FIELD;
196  if (s->mb_intra) {
197  mv_block->macroblock_type = XVMC_MB_TYPE_INTRA; // no MC, all done
198  } else {
199  mv_block->macroblock_type = XVMC_MB_TYPE_PATTERN;
200 
201  if (s->mv_dir & MV_DIR_FORWARD) {
202  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_FORWARD;
203  // PMV[n][dir][xy] = mv[dir][n][xy]
204  mv_block->PMV[0][0][0] = s->mv[0][0][0];
205  mv_block->PMV[0][0][1] = s->mv[0][0][1];
206  mv_block->PMV[1][0][0] = s->mv[0][1][0];
207  mv_block->PMV[1][0][1] = s->mv[0][1][1];
208  }
209  if (s->mv_dir & MV_DIR_BACKWARD) {
210  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_BACKWARD;
211  mv_block->PMV[0][1][0] = s->mv[1][0][0];
212  mv_block->PMV[0][1][1] = s->mv[1][0][1];
213  mv_block->PMV[1][1][0] = s->mv[1][1][0];
214  mv_block->PMV[1][1][1] = s->mv[1][1][1];
215  }
216 
217  switch(s->mv_type) {
218  case MV_TYPE_16X16:
219  mv_block->motion_type = XVMC_PREDICTION_FRAME;
220  break;
221  case MV_TYPE_16X8:
222  mv_block->motion_type = XVMC_PREDICTION_16x8;
223  break;
224  case MV_TYPE_FIELD:
225  mv_block->motion_type = XVMC_PREDICTION_FIELD;
226  if (s->picture_structure == PICT_FRAME) {
227  mv_block->PMV[0][0][1] <<= 1;
228  mv_block->PMV[1][0][1] <<= 1;
229  mv_block->PMV[0][1][1] <<= 1;
230  mv_block->PMV[1][1][1] <<= 1;
231  }
232  break;
233  case MV_TYPE_DMV:
234  mv_block->motion_type = XVMC_PREDICTION_DUAL_PRIME;
235  if (s->picture_structure == PICT_FRAME) {
236 
237  mv_block->PMV[0][0][0] = s->mv[0][0][0]; // top from top
238  mv_block->PMV[0][0][1] = s->mv[0][0][1] << 1;
239 
240  mv_block->PMV[0][1][0] = s->mv[0][0][0]; // bottom from bottom
241  mv_block->PMV[0][1][1] = s->mv[0][0][1] << 1;
242 
243  mv_block->PMV[1][0][0] = s->mv[0][2][0]; // dmv00, top from bottom
244  mv_block->PMV[1][0][1] = s->mv[0][2][1] << 1; // dmv01
245 
246  mv_block->PMV[1][1][0] = s->mv[0][3][0]; // dmv10, bottom from top
247  mv_block->PMV[1][1][1] = s->mv[0][3][1] << 1; // dmv11
248 
249  } else {
250  mv_block->PMV[0][1][0] = s->mv[0][2][0]; // dmv00
251  mv_block->PMV[0][1][1] = s->mv[0][2][1]; // dmv01
252  }
253  break;
254  default:
255  assert(0);
256  }
257 
258  mv_block->motion_vertical_field_select = 0;
259 
260  // set correct field references
261  if (s->mv_type == MV_TYPE_FIELD || s->mv_type == MV_TYPE_16X8) {
262  mv_block->motion_vertical_field_select |= s->field_select[0][0];
263  mv_block->motion_vertical_field_select |= s->field_select[1][0] << 1;
264  mv_block->motion_vertical_field_select |= s->field_select[0][1] << 2;
265  mv_block->motion_vertical_field_select |= s->field_select[1][1] << 3;
266  }
267  } // !intra
268  // time to handle data blocks
269  mv_block->index = render->next_free_data_block_num;
270 
271  blocks_per_mb = 6;
272  if (s->chroma_format >= 2) {
273  blocks_per_mb = 4 + (1 << s->chroma_format);
274  }
275 
276  // calculate cbp
277  cbp = 0;
278  for (i = 0; i < blocks_per_mb; i++) {
279  cbp += cbp;
280  if (s->block_last_index[i] >= 0)
281  cbp++;
282  }
283 
284  if (s->flags & CODEC_FLAG_GRAY) {
285  if (s->mb_intra) { // intra frames are always full chroma blocks
286  for (i = 4; i < blocks_per_mb; i++) {
287  memset(s->pblocks[i], 0, sizeof(*s->pblocks[i])); // so we need to clear them
288  if (!render->unsigned_intra)
289  *s->pblocks[i][0] = 1 << 10;
290  }
291  } else {
292  cbp &= 0xf << (blocks_per_mb - 4);
293  blocks_per_mb = 4; // luminance blocks only
294  }
295  }
296  mv_block->coded_block_pattern = cbp;
297  if (cbp == 0)
298  mv_block->macroblock_type &= ~XVMC_MB_TYPE_PATTERN;
299 
300  for (i = 0; i < blocks_per_mb; i++) {
301  if (s->block_last_index[i] >= 0) {
302  // I do not have unsigned_intra MOCO to test, hope it is OK.
303  if (s->mb_intra && (render->idct || !render->unsigned_intra))
304  *s->pblocks[i][0] -= 1 << 10;
305  if (!render->idct) {
306  s->dsp.idct(*s->pblocks[i]);
307  /* It is unclear if MC hardware requires pixel diff values to be
308  * in the range [-255;255]. TODO: Clipping if such hardware is
309  * ever found. As of now it would only be an unnecessary
310  * slowdown. */
311  }
312  // copy blocks only if the codec doesn't support pblocks reordering
313  if (s->avctx->xvmc_acceleration == 1) {
314  memcpy(&render->data_blocks[render->next_free_data_block_num*64],
315  s->pblocks[i], sizeof(*s->pblocks[i]));
316  }
317  render->next_free_data_block_num++;
318  }
319  }
320  render->filled_mv_blocks_num++;
321 
322  assert(render->filled_mv_blocks_num <= render->allocated_mv_blocks);
323  assert(render->next_free_data_block_num <= render->allocated_data_blocks);
324  /* The above conditions should not be able to fail as long as this function
325  * is used and the following 'if ()' automatically calls a callback to free
326  * blocks. */
327 
328 
329  if (render->filled_mv_blocks_num == render->allocated_mv_blocks)
330  ff_mpeg_draw_horiz_band(s, 0, 0);
331 }