path: root/libavcodec/mpegpicture.c (plain)
blob: 302f9d20d37060e714c520842b7b73a2bacd7bb8

1	/*
2	* Mpeg video formats-related picture management functions
3	*
4	* This file is part of FFmpeg.
5	*
6	* FFmpeg is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU Lesser General Public
8	* License as published by the Free Software Foundation; either
9	* version 2.1 of the License, or (at your option) any later version.
10	*
11	* FFmpeg is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14	* Lesser General Public License for more details.
15	*
16	* You should have received a copy of the GNU Lesser General Public
17	* License along with FFmpeg; if not, write to the Free Software
18	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19	*/
20
21	#include <stdint.h>
22
23	#include "libavutil/avassert.h"
24	#include "libavutil/common.h"
25
26	#include "avcodec.h"
27	#include "motion_est.h"
28	#include "mpegpicture.h"
29	#include "mpegutils.h"
30
31	static int make_tables_writable(Picture *pic)
32	{
33	int ret, i;
34	#define MAKE_WRITABLE(table) \
35	do {\
36	if (pic->table &&\
37	(ret = av_buffer_make_writable(&pic->table)) < 0)\
38	return ret;\
39	} while (0)
40
41	MAKE_WRITABLE(mb_var_buf);
42	MAKE_WRITABLE(mc_mb_var_buf);
43	MAKE_WRITABLE(mb_mean_buf);
44	MAKE_WRITABLE(mbskip_table_buf);
45	MAKE_WRITABLE(qscale_table_buf);
46	MAKE_WRITABLE(mb_type_buf);
47
48	for (i = 0; i < 2; i++) {
49	MAKE_WRITABLE(motion_val_buf[i]);
50	MAKE_WRITABLE(ref_index_buf[i]);
51	}
52
53	return 0;
54	}
55
56	int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
57	ScratchpadContext *sc, int linesize)
58	{
59	int alloc_size = FFALIGN(FFABS(linesize) + 64, 32);
60
61	if (avctx->hwaccel
62	#if FF_API_CAP_VDPAU
63	|| avctx->codec->capabilities & AV_CODEC_CAP_HWACCEL_VDPAU
64	#endif
65	)
66	return 0;
67
68	if (linesize < 24) {
69	av_log(avctx, AV_LOG_ERROR, "Image too small, temporary buffers cannot function\n");
70	return AVERROR_PATCHWELCOME;
71	}
72
73	// edge emu needs blocksize + filter length - 1
74	// (= 17x17 for halfpel / 21x21 for H.264)
75	// VC-1 computes luma and chroma simultaneously and needs 19X19 + 9x9
76	// at uvlinesize. It supports only YUV420 so 24x24 is enough
77	// linesize * interlaced * MBsize
78	// we also use this buffer for encoding in encode_mb_internal() needig an additional 32 lines
79	FF_ALLOCZ_ARRAY_OR_GOTO(avctx, sc->edge_emu_buffer, alloc_size, 4 * 70,
80	fail);
81
82	FF_ALLOCZ_ARRAY_OR_GOTO(avctx, me->scratchpad, alloc_size, 4 * 16 * 2,
83	fail)
84	me->temp = me->scratchpad;
85	sc->rd_scratchpad = me->scratchpad;
86	sc->b_scratchpad = me->scratchpad;
87	sc->obmc_scratchpad = me->scratchpad + 16;
88
89	return 0;
90	fail:
91	av_freep(&sc->edge_emu_buffer);
92	return AVERROR(ENOMEM);
93	}
94
95	/**
96	* Allocate a frame buffer
97	*/
98	static int alloc_frame_buffer(AVCodecContext *avctx, Picture *pic,
99	MotionEstContext *me, ScratchpadContext *sc,
100	int chroma_x_shift, int chroma_y_shift,
101	int linesize, int uvlinesize)
102	{
103	int edges_needed = av_codec_is_encoder(avctx->codec);
104	int r, ret;
105
106	pic->tf.f = pic->f;
107	if (avctx->codec_id != AV_CODEC_ID_WMV3IMAGE &&
108	avctx->codec_id != AV_CODEC_ID_VC1IMAGE &&
109	avctx->codec_id != AV_CODEC_ID_MSS2) {
110	if (edges_needed) {
111	pic->f->width = avctx->width + 2 * EDGE_WIDTH;
112	pic->f->height = avctx->height + 2 * EDGE_WIDTH;
113	}
114
115	r = ff_thread_get_buffer(avctx, &pic->tf,
116	pic->reference ? AV_GET_BUFFER_FLAG_REF : 0);
117	} else {
118	pic->f->width = avctx->width;
119	pic->f->height = avctx->height;
120	pic->f->format = avctx->pix_fmt;
121	r = avcodec_default_get_buffer2(avctx, pic->f, 0);
122	}
123
124	if (r < 0 || !pic->f->buf[0]) {
125	av_log(avctx, AV_LOG_ERROR, "get_buffer() failed (%d %p)\n",
126	r, pic->f->data[0]);
127	return -1;
128	}
129
130	if (edges_needed) {
131	int i;
132	for (i = 0; pic->f->data[i]; i++) {
133	int offset = (EDGE_WIDTH >> (i ? chroma_y_shift : 0)) *
134	pic->f->linesize[i] +
135	(EDGE_WIDTH >> (i ? chroma_x_shift : 0));
136	pic->f->data[i] += offset;
137	}
138	pic->f->width = avctx->width;
139	pic->f->height = avctx->height;
140	}
141
142	if (avctx->hwaccel) {
143	assert(!pic->hwaccel_picture_private);
144	if (avctx->hwaccel->frame_priv_data_size) {
145	pic->hwaccel_priv_buf = av_buffer_allocz(avctx->hwaccel->frame_priv_data_size);
146	if (!pic->hwaccel_priv_buf) {
147	av_log(avctx, AV_LOG_ERROR, "alloc_frame_buffer() failed (hwaccel private data allocation)\n");
148	return -1;
149	}
150	pic->hwaccel_picture_private = pic->hwaccel_priv_buf->data;
151	}
152	}
153
154	if (linesize && (linesize != pic->f->linesize[0] ||
155	uvlinesize != pic->f->linesize[1])) {
156	av_log(avctx, AV_LOG_ERROR,
157	"get_buffer() failed (stride changed)\n");
158	ff_mpeg_unref_picture(avctx, pic);
159	return -1;
160	}
161
162	if (pic->f->linesize[1] != pic->f->linesize[2]) {
163	av_log(avctx, AV_LOG_ERROR,
164	"get_buffer() failed (uv stride mismatch)\n");
165	ff_mpeg_unref_picture(avctx, pic);
166	return -1;
167	}
168
169	if (!sc->edge_emu_buffer &&
170	(ret = ff_mpeg_framesize_alloc(avctx, me, sc,
171	pic->f->linesize[0])) < 0) {
172	av_log(avctx, AV_LOG_ERROR,
173	"get_buffer() failed to allocate context scratch buffers.\n");
174	ff_mpeg_unref_picture(avctx, pic);
175	return ret;
176	}
177
178	return 0;
179	}
180
181	static int alloc_picture_tables(AVCodecContext *avctx, Picture *pic, int encoding, int out_format,
182	int mb_stride, int mb_width, int mb_height, int b8_stride)
183	{
184	const int big_mb_num = mb_stride * (mb_height + 1) + 1;
185	const int mb_array_size = mb_stride * mb_height;
186	const int b8_array_size = b8_stride * mb_height * 2;
187	int i;
188
189
190	pic->mbskip_table_buf = av_buffer_allocz(mb_array_size + 2);
191	pic->qscale_table_buf = av_buffer_allocz(big_mb_num + mb_stride);
192	pic->mb_type_buf = av_buffer_allocz((big_mb_num + mb_stride) *
193	sizeof(uint32_t));
194	if (!pic->mbskip_table_buf || !pic->qscale_table_buf || !pic->mb_type_buf)
195	return AVERROR(ENOMEM);
196
197	if (encoding) {
198	pic->mb_var_buf = av_buffer_allocz(mb_array_size * sizeof(int16_t));
199	pic->mc_mb_var_buf = av_buffer_allocz(mb_array_size * sizeof(int16_t));
200	pic->mb_mean_buf = av_buffer_allocz(mb_array_size);
201	if (!pic->mb_var_buf || !pic->mc_mb_var_buf || !pic->mb_mean_buf)
202	return AVERROR(ENOMEM);
203	}
204
205	if (out_format == FMT_H263 || encoding || avctx->debug_mv ||
206	(avctx->flags2 & AV_CODEC_FLAG2_EXPORT_MVS)) {
207	int mv_size = 2 * (b8_array_size + 4) * sizeof(int16_t);
208	int ref_index_size = 4 * mb_array_size;
209
210	for (i = 0; mv_size && i < 2; i++) {
211	pic->motion_val_buf[i] = av_buffer_allocz(mv_size);
212	pic->ref_index_buf[i] = av_buffer_allocz(ref_index_size);
213	if (!pic->motion_val_buf[i] || !pic->ref_index_buf[i])
214	return AVERROR(ENOMEM);
215	}
216	}
217
218	pic->alloc_mb_width = mb_width;
219	pic->alloc_mb_height = mb_height;
220
221	return 0;
222	}
223
224	/**
225	* Allocate a Picture.
226	* The pixels are allocated/set by calling get_buffer() if shared = 0
227	*/
228	int ff_alloc_picture(AVCodecContext *avctx, Picture *pic, MotionEstContext *me,
229	ScratchpadContext *sc, int shared, int encoding,
230	int chroma_x_shift, int chroma_y_shift, int out_format,
231	int mb_stride, int mb_width, int mb_height, int b8_stride,
232	ptrdiff_t *linesize, ptrdiff_t *uvlinesize)
233	{
234	int i, ret;
235
236	if (pic->qscale_table_buf)
237	if ( pic->alloc_mb_width != mb_width
238	|| pic->alloc_mb_height != mb_height)
239	ff_free_picture_tables(pic);
240
241	if (shared) {
242	av_assert0(pic->f->data[0]);
243	pic->shared = 1;
244	} else {
245	av_assert0(!pic->f->buf[0]);
246	if (alloc_frame_buffer(avctx, pic, me, sc,
247	chroma_x_shift, chroma_y_shift,
248	*linesize, *uvlinesize) < 0)
249	return -1;
250
251	*linesize = pic->f->linesize[0];
252	*uvlinesize = pic->f->linesize[1];
253	}
254
255	if (!pic->qscale_table_buf)
256	ret = alloc_picture_tables(avctx, pic, encoding, out_format,
257	mb_stride, mb_width, mb_height, b8_stride);
258	else
259	ret = make_tables_writable(pic);
260	if (ret < 0)
261	goto fail;
262
263	if (encoding) {
264	pic->mb_var = (uint16_t*)pic->mb_var_buf->data;
265	pic->mc_mb_var = (uint16_t*)pic->mc_mb_var_buf->data;
266	pic->mb_mean = pic->mb_mean_buf->data;
267	}
268
269	pic->mbskip_table = pic->mbskip_table_buf->data;
270	pic->qscale_table = pic->qscale_table_buf->data + 2 * mb_stride + 1;
271	pic->mb_type = (uint32_t*)pic->mb_type_buf->data + 2 * mb_stride + 1;
272
273	if (pic->motion_val_buf[0]) {
274	for (i = 0; i < 2; i++) {
275	pic->motion_val[i] = (int16_t (*)[2])pic->motion_val_buf[i]->data + 4;
276	pic->ref_index[i] = pic->ref_index_buf[i]->data;
277	}
278	}
279
280	return 0;
281	fail:
282	av_log(avctx, AV_LOG_ERROR, "Error allocating a picture.\n");
283	ff_mpeg_unref_picture(avctx, pic);
284	ff_free_picture_tables(pic);
285	return AVERROR(ENOMEM);
286	}
287
288	/**
289	* Deallocate a picture.
290	*/
291	void ff_mpeg_unref_picture(AVCodecContext *avctx, Picture *pic)
292	{
293	int off = offsetof(Picture, mb_mean) + sizeof(pic->mb_mean);
294
295	pic->tf.f = pic->f;
296	/* WM Image / Screen codecs allocate internal buffers with different
297	* dimensions / colorspaces; ignore user-defined callbacks for these. */
298	if (avctx->codec_id != AV_CODEC_ID_WMV3IMAGE &&
299	avctx->codec_id != AV_CODEC_ID_VC1IMAGE &&
300	avctx->codec_id != AV_CODEC_ID_MSS2)
301	ff_thread_release_buffer(avctx, &pic->tf);
302	else if (pic->f)
303	av_frame_unref(pic->f);
304
305	av_buffer_unref(&pic->hwaccel_priv_buf);
306
307	if (pic->needs_realloc)
308	ff_free_picture_tables(pic);
309
310	memset((uint8_t*)pic + off, 0, sizeof(*pic) - off);
311	}
312
313	int ff_update_picture_tables(Picture *dst, Picture *src)
314	{
315	int i;
316
317	#define UPDATE_TABLE(table) \
318	do { \
319	if (src->table && \
320	(!dst->table || dst->table->buffer != src->table->buffer)) { \
321	av_buffer_unref(&dst->table); \
322	dst->table = av_buffer_ref(src->table); \
323	if (!dst->table) { \
324	ff_free_picture_tables(dst); \
325	return AVERROR(ENOMEM); \
326	} \
327	} \
328	} while (0)
329
330	UPDATE_TABLE(mb_var_buf);
331	UPDATE_TABLE(mc_mb_var_buf);
332	UPDATE_TABLE(mb_mean_buf);
333	UPDATE_TABLE(mbskip_table_buf);
334	UPDATE_TABLE(qscale_table_buf);
335	UPDATE_TABLE(mb_type_buf);
336	for (i = 0; i < 2; i++) {
337	UPDATE_TABLE(motion_val_buf[i]);
338	UPDATE_TABLE(ref_index_buf[i]);
339	}
340
341	dst->mb_var = src->mb_var;
342	dst->mc_mb_var = src->mc_mb_var;
343	dst->mb_mean = src->mb_mean;
344	dst->mbskip_table = src->mbskip_table;
345	dst->qscale_table = src->qscale_table;
346	dst->mb_type = src->mb_type;
347	for (i = 0; i < 2; i++) {
348	dst->motion_val[i] = src->motion_val[i];
349	dst->ref_index[i] = src->ref_index[i];
350	}
351
352	dst->alloc_mb_width = src->alloc_mb_width;
353	dst->alloc_mb_height = src->alloc_mb_height;
354
355	return 0;
356	}
357
358	int ff_mpeg_ref_picture(AVCodecContext *avctx, Picture *dst, Picture *src)
359	{
360	int ret;
361
362	av_assert0(!dst->f->buf[0]);
363	av_assert0(src->f->buf[0]);
364
365	src->tf.f = src->f;
366	dst->tf.f = dst->f;
367	ret = ff_thread_ref_frame(&dst->tf, &src->tf);
368	if (ret < 0)
369	goto fail;
370
371	ret = ff_update_picture_tables(dst, src);
372	if (ret < 0)
373	goto fail;
374
375	if (src->hwaccel_picture_private) {
376	dst->hwaccel_priv_buf = av_buffer_ref(src->hwaccel_priv_buf);
377	if (!dst->hwaccel_priv_buf)
378	goto fail;
379	dst->hwaccel_picture_private = dst->hwaccel_priv_buf->data;
380	}
381
382	dst->field_picture = src->field_picture;
383	dst->mb_var_sum = src->mb_var_sum;
384	dst->mc_mb_var_sum = src->mc_mb_var_sum;
385	dst->b_frame_score = src->b_frame_score;
386	dst->needs_realloc = src->needs_realloc;
387	dst->reference = src->reference;
388	dst->shared = src->shared;
389
390	memcpy(dst->encoding_error, src->encoding_error,
391	sizeof(dst->encoding_error));
392
393	return 0;
394	fail:
395	ff_mpeg_unref_picture(avctx, dst);
396	return ret;
397	}
398
399	static inline int pic_is_unused(Picture *pic)
400	{
401	if (!pic->f->buf[0])
402	return 1;
403	if (pic->needs_realloc && !(pic->reference & DELAYED_PIC_REF))
404	return 1;
405	return 0;
406	}
407
408	static int find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared)
409	{
410	int i;
411
412	if (shared) {
413	for (i = 0; i < MAX_PICTURE_COUNT; i++) {
414	if (!picture[i].f->buf[0])
415	return i;
416	}
417	} else {
418	for (i = 0; i < MAX_PICTURE_COUNT; i++) {
419	if (pic_is_unused(&picture[i]))
420	return i;
421	}
422	}
423
424	av_log(avctx, AV_LOG_FATAL,
425	"Internal error, picture buffer overflow\n");
426	/* We could return -1, but the codec would crash trying to draw into a
427	* non-existing frame anyway. This is safer than waiting for a random crash.
428	* Also the return of this is never useful, an encoder must only allocate
429	* as much as allowed in the specification. This has no relationship to how
430	* much libavcodec could allocate (and MAX_PICTURE_COUNT is always large
431	* enough for such valid streams).
432	* Plus, a decoder has to check stream validity and remove frames if too
433	* many reference frames are around. Waiting for "OOM" is not correct at
434	* all. Similarly, missing reference frames have to be replaced by
435	* interpolated/MC frames, anything else is a bug in the codec ...
436	*/
437	abort();
438	return -1;
439	}
440
441	int ff_find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared)
442	{
443	int ret = find_unused_picture(avctx, picture, shared);
444
445	if (ret >= 0 && ret < MAX_PICTURE_COUNT) {
446	if (picture[ret].needs_realloc) {
447	picture[ret].needs_realloc = 0;
448	ff_free_picture_tables(&picture[ret]);
449	ff_mpeg_unref_picture(avctx, &picture[ret]);
450	}
451	}
452	return ret;
453	}
454
455	void ff_free_picture_tables(Picture *pic)
456	{
457	int i;
458
459	pic->alloc_mb_width =
460	pic->alloc_mb_height = 0;
461
462	av_buffer_unref(&pic->mb_var_buf);
463	av_buffer_unref(&pic->mc_mb_var_buf);
464	av_buffer_unref(&pic->mb_mean_buf);
465	av_buffer_unref(&pic->mbskip_table_buf);
466	av_buffer_unref(&pic->qscale_table_buf);
467	av_buffer_unref(&pic->mb_type_buf);
468
469	for (i = 0; i < 2; i++) {
470	av_buffer_unref(&pic->motion_val_buf[i]);
471	av_buffer_unref(&pic->ref_index_buf[i]);
472	}
473	}
474