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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 "mpegvideo.h"
27 
28 #undef NDEBUG
29 #include <assert.h>
30 
31 #include "xvmc.h"
32 #include "xvmc_internal.h"
33 #include "version.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 = (int16_t (*)[64])(render->data_blocks + render->next_free_data_block_num * 64);
48 }
49 
51 {
52  int16_t (*tmp)[64];
53 
54  tmp = s->pblocks[4];
55  s->pblocks[4] = s->pblocks[5];
56  s->pblocks[5] = tmp;
57 }
58 
59 /**
60  * Fill individual block pointers, so there are no gaps in the data_block array
61  * in case not all blocks in the macroblock are coded.
62  */
64 {
65  int i, j = 0;
66  const int mb_block_count = 4 + (1 << s->chroma_format);
67 
68  cbp <<= 12-mb_block_count;
69  for (i = 0; i < mb_block_count; i++) {
70  if (cbp & (1 << 11))
71  s->pblocks[i] = &s->block[j++];
72  else
73  s->pblocks[i] = NULL;
74  cbp += cbp;
75  }
76  if (s->swap_uv) {
77  exchange_uv(s);
78  }
79 }
80 
81 /**
82  * Find and store the surfaces that are used as reference frames.
83  * This function should be called for every new field and/or frame.
84  * It should be safe to call the function a few times for the same field.
85  */
86 static int ff_xvmc_field_start(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
87 {
88  struct MpegEncContext *s = avctx->priv_data;
89  struct xvmc_pix_fmt *last, *next, *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
90  const int mb_block_count = 4 + (1 << s->chroma_format);
91 
92  assert(avctx);
93  if (!render || render->xvmc_id != AV_XVMC_ID ||
94  !render->data_blocks || !render->mv_blocks ||
95  (unsigned int)render->allocated_mv_blocks > INT_MAX/(64*6) ||
96  (unsigned int)render->allocated_data_blocks > INT_MAX/64 ||
97  !render->p_surface) {
98  av_log(avctx, AV_LOG_ERROR,
99  "Render token doesn't look as expected.\n");
100  return -1; // make sure that this is a render packet
101  }
102 
103  if (render->filled_mv_blocks_num) {
104  av_log(avctx, AV_LOG_ERROR,
105  "Rendering surface contains %i unprocessed blocks.\n",
106  render->filled_mv_blocks_num);
107  return -1;
108  }
109  if (render->allocated_mv_blocks < 1 ||
110  render->allocated_data_blocks < render->allocated_mv_blocks*mb_block_count ||
111  render->start_mv_blocks_num >= render->allocated_mv_blocks ||
112  render->next_free_data_block_num >
113  render->allocated_data_blocks -
114  mb_block_count*(render->allocated_mv_blocks-render->start_mv_blocks_num)) {
115  av_log(avctx, AV_LOG_ERROR,
116  "Rendering surface doesn't provide enough block structures to work with.\n");
117  return -1;
118  }
119 
121  render->flags = s->first_field ? 0 : XVMC_SECOND_FIELD;
122  render->p_future_surface = NULL;
123  render->p_past_surface = NULL;
124 
125  switch(s->pict_type) {
126  case AV_PICTURE_TYPE_I:
127  return 0; // no prediction from other frames
128  case AV_PICTURE_TYPE_B:
129  next = (struct xvmc_pix_fmt*)s->next_picture.f.data[2];
130  if (!next)
131  return -1;
132  if (next->xvmc_id != AV_XVMC_ID)
133  return -1;
134  render->p_future_surface = next->p_surface;
135  // no return here, going to set forward prediction
136  case AV_PICTURE_TYPE_P:
137  last = (struct xvmc_pix_fmt*)s->last_picture.f.data[2];
138  if (!last)
139  last = render; // predict second field from the first
140  if (last->xvmc_id != AV_XVMC_ID)
141  return -1;
142  render->p_past_surface = last->p_surface;
143  return 0;
144  }
145 
146 return -1;
147 }
148 
149 /**
150  * Complete frame/field rendering by passing any remaining blocks.
151  * Normally ff_draw_horiz_band() is called for each slice, however,
152  * some leftover blocks, for example from error_resilience(), may remain.
153  * It should be safe to call the function a few times for the same field.
154  */
156 {
157  struct MpegEncContext *s = avctx->priv_data;
158  struct xvmc_pix_fmt *render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
159  assert(render);
160 
161  if (render->filled_mv_blocks_num > 0)
162  ff_mpeg_draw_horiz_band(s, 0, 0);
163  return 0;
164 }
165 
166 /**
167  * Synthesize the data needed by XvMC to render one macroblock of data.
168  * Fill all relevant fields, if necessary do IDCT.
169  */
170 static void ff_xvmc_decode_mb(struct MpegEncContext *s)
171 {
172  XvMCMacroBlock *mv_block;
173  struct xvmc_pix_fmt *render;
174  int i, cbp, blocks_per_mb;
175 
176  const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
177 
178 
179  if (s->encoding) {
180  av_log(s->avctx, AV_LOG_ERROR, "XVMC doesn't support encoding!!!\n");
181  return;
182  }
183 
184  // from MPV_decode_mb(), update DC predictors for P macroblocks
185  if (!s->mb_intra) {
186  s->last_dc[0] =
187  s->last_dc[1] =
188  s->last_dc[2] = 128 << s->intra_dc_precision;
189  }
190 
191  // MC doesn't skip blocks
192  s->mb_skipped = 0;
193 
194 
195  // Do I need to export quant when I could not perform postprocessing?
196  // Anyway, it doesn't hurt.
197  s->current_picture.qscale_table[mb_xy] = s->qscale;
198 
199  // start of XVMC-specific code
200  render = (struct xvmc_pix_fmt*)s->current_picture.f.data[2];
201  assert(render);
202  assert(render->xvmc_id == AV_XVMC_ID);
203  assert(render->mv_blocks);
204 
205  // take the next free macroblock
206  mv_block = &render->mv_blocks[render->start_mv_blocks_num +
207  render->filled_mv_blocks_num];
208 
209  mv_block->x = s->mb_x;
210  mv_block->y = s->mb_y;
211  mv_block->dct_type = s->interlaced_dct; // XVMC_DCT_TYPE_FRAME/FIELD;
212  if (s->mb_intra) {
213  mv_block->macroblock_type = XVMC_MB_TYPE_INTRA; // no MC, all done
214  } else {
215  mv_block->macroblock_type = XVMC_MB_TYPE_PATTERN;
216 
217  if (s->mv_dir & MV_DIR_FORWARD) {
218  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_FORWARD;
219  // PMV[n][dir][xy] = mv[dir][n][xy]
220  mv_block->PMV[0][0][0] = s->mv[0][0][0];
221  mv_block->PMV[0][0][1] = s->mv[0][0][1];
222  mv_block->PMV[1][0][0] = s->mv[0][1][0];
223  mv_block->PMV[1][0][1] = s->mv[0][1][1];
224  }
225  if (s->mv_dir & MV_DIR_BACKWARD) {
226  mv_block->macroblock_type |= XVMC_MB_TYPE_MOTION_BACKWARD;
227  mv_block->PMV[0][1][0] = s->mv[1][0][0];
228  mv_block->PMV[0][1][1] = s->mv[1][0][1];
229  mv_block->PMV[1][1][0] = s->mv[1][1][0];
230  mv_block->PMV[1][1][1] = s->mv[1][1][1];
231  }
232 
233  switch(s->mv_type) {
234  case MV_TYPE_16X16:
235  mv_block->motion_type = XVMC_PREDICTION_FRAME;
236  break;
237  case MV_TYPE_16X8:
238  mv_block->motion_type = XVMC_PREDICTION_16x8;
239  break;
240  case MV_TYPE_FIELD:
241  mv_block->motion_type = XVMC_PREDICTION_FIELD;
242  if (s->picture_structure == PICT_FRAME) {
243  mv_block->PMV[0][0][1] <<= 1;
244  mv_block->PMV[1][0][1] <<= 1;
245  mv_block->PMV[0][1][1] <<= 1;
246  mv_block->PMV[1][1][1] <<= 1;
247  }
248  break;
249  case MV_TYPE_DMV:
250  mv_block->motion_type = XVMC_PREDICTION_DUAL_PRIME;
251  if (s->picture_structure == PICT_FRAME) {
252 
253  mv_block->PMV[0][0][0] = s->mv[0][0][0]; // top from top
254  mv_block->PMV[0][0][1] = s->mv[0][0][1] << 1;
255 
256  mv_block->PMV[0][1][0] = s->mv[0][0][0]; // bottom from bottom
257  mv_block->PMV[0][1][1] = s->mv[0][0][1] << 1;
258 
259  mv_block->PMV[1][0][0] = s->mv[0][2][0]; // dmv00, top from bottom
260  mv_block->PMV[1][0][1] = s->mv[0][2][1] << 1; // dmv01
261 
262  mv_block->PMV[1][1][0] = s->mv[0][3][0]; // dmv10, bottom from top
263  mv_block->PMV[1][1][1] = s->mv[0][3][1] << 1; // dmv11
264 
265  } else {
266  mv_block->PMV[0][1][0] = s->mv[0][2][0]; // dmv00
267  mv_block->PMV[0][1][1] = s->mv[0][2][1]; // dmv01
268  }
269  break;
270  default:
271  assert(0);
272  }
273 
274  mv_block->motion_vertical_field_select = 0;
275 
276  // set correct field references
277  if (s->mv_type == MV_TYPE_FIELD || s->mv_type == MV_TYPE_16X8) {
278  mv_block->motion_vertical_field_select |= s->field_select[0][0];
279  mv_block->motion_vertical_field_select |= s->field_select[1][0] << 1;
280  mv_block->motion_vertical_field_select |= s->field_select[0][1] << 2;
281  mv_block->motion_vertical_field_select |= s->field_select[1][1] << 3;
282  }
283  } // !intra
284  // time to handle data blocks
285  mv_block->index = render->next_free_data_block_num;
286 
287  blocks_per_mb = 6;
288  if (s->chroma_format >= 2) {
289  blocks_per_mb = 4 + (1 << s->chroma_format);
290  }
291 
292  // calculate cbp
293  cbp = 0;
294  for (i = 0; i < blocks_per_mb; i++) {
295  cbp += cbp;
296  if (s->block_last_index[i] >= 0)
297  cbp++;
298  }
299 
300  if (s->flags & CODEC_FLAG_GRAY) {
301  if (s->mb_intra) { // intra frames are always full chroma blocks
302  for (i = 4; i < blocks_per_mb; i++) {
303  memset(s->pblocks[i], 0, sizeof(*s->pblocks[i])); // so we need to clear them
304  if (!render->unsigned_intra)
305  *s->pblocks[i][0] = 1 << 10;
306  }
307  } else {
308  cbp &= 0xf << (blocks_per_mb - 4);
309  blocks_per_mb = 4; // luminance blocks only
310  }
311  }
312  mv_block->coded_block_pattern = cbp;
313  if (cbp == 0)
314  mv_block->macroblock_type &= ~XVMC_MB_TYPE_PATTERN;
315 
316  for (i = 0; i < blocks_per_mb; i++) {
317  if (s->block_last_index[i] >= 0) {
318  // I do not have unsigned_intra MOCO to test, hope it is OK.
319  if (s->mb_intra && (render->idct || !render->unsigned_intra))
320  *s->pblocks[i][0] -= 1 << 10;
321  if (!render->idct) {
322  s->dsp.idct(*s->pblocks[i]);
323  /* It is unclear if MC hardware requires pixel diff values to be
324  * in the range [-255;255]. TODO: Clipping if such hardware is
325  * ever found. As of now it would only be an unnecessary
326  * slowdown. */
327  }
328  // copy blocks only if the codec doesn't support pblocks reordering
329  if (!s->pack_pblocks) {
330  memcpy(&render->data_blocks[render->next_free_data_block_num*64],
331  s->pblocks[i], sizeof(*s->pblocks[i]));
332  }
333  render->next_free_data_block_num++;
334  }
335  }
336  render->filled_mv_blocks_num++;
337 
338  assert(render->filled_mv_blocks_num <= render->allocated_mv_blocks);
339  assert(render->next_free_data_block_num <= render->allocated_data_blocks);
340  /* The above conditions should not be able to fail as long as this function
341  * is used and the following 'if ()' automatically calls a callback to free
342  * blocks. */
343 
344 
345  if (render->filled_mv_blocks_num == render->allocated_mv_blocks)
346  ff_mpeg_draw_horiz_band(s, 0, 0);
347 }
348 
349 #if CONFIG_MPEG1_XVMC_HWACCEL
350 AVHWAccel ff_mpeg1_xvmc_hwaccel = {
351  .name = "mpeg1_xvmc",
352  .type = AVMEDIA_TYPE_VIDEO,
354  .pix_fmt = AV_PIX_FMT_XVMC,
355  .start_frame = ff_xvmc_field_start,
356  .end_frame = ff_xvmc_field_end,
357  .decode_slice = NULL,
358  .decode_mb = ff_xvmc_decode_mb,
359  .priv_data_size = 0,
360 };
361 #endif
362 
363 #if CONFIG_MPEG2_XVMC_HWACCEL
364 AVHWAccel ff_mpeg2_xvmc_hwaccel = {
365  .name = "mpeg2_xvmc",
366  .type = AVMEDIA_TYPE_VIDEO,
368  .pix_fmt = AV_PIX_FMT_XVMC,
369  .start_frame = ff_xvmc_field_start,
370  .end_frame = ff_xvmc_field_end,
371  .decode_slice = NULL,
372  .decode_mb = ff_xvmc_decode_mb,
373  .priv_data_size = 0,
374 };
375 #endif