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eatgv.c
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1 /*
2  * Electronic Arts TGV Video Decoder
3  * Copyright (c) 2007-2008 Peter Ross
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 St, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Electronic Arts TGV Video Decoder
25  * by Peter Ross (pross@xvid.org)
26  *
27  * Technical details here:
28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGV
29  */
30 
31 #include "libavutil/imgutils.h"
32 #include "libavutil/mem.h"
33 
34 #define BITSTREAM_READER_LE
35 #include "avcodec.h"
36 #include "get_bits.h"
37 #include "internal.h"
38 
39 #define EA_PREAMBLE_SIZE 8
40 #define kVGT_TAG MKTAG('k', 'V', 'G', 'T')
41 
42 typedef struct TgvContext {
48 
49  int (*mv_codebook)[2];
51  int num_mvs; ///< current length of mv_codebook
52  int num_blocks_packed; ///< current length of block_codebook
53 } TgvContext;
54 
56 {
57  TgvContext *s = avctx->priv_data;
58  s->avctx = avctx;
59  avctx->framerate = (AVRational){ 15, 1 };
60  avctx->pix_fmt = AV_PIX_FMT_PAL8;
61 
63  if (!s->last_frame)
64  return AVERROR(ENOMEM);
65 
66  return 0;
67 }
68 
69 /**
70  * Unpack buffer
71  * @return 0 on success, -1 on critical buffer underflow
72  */
73 static int unpack(const uint8_t *src, const uint8_t *src_end,
74  uint8_t *dst, int width, int height)
75 {
76  uint8_t *dst_end = dst + width*height;
77  int size, size1, size2, offset, run;
78  uint8_t *dst_start = dst;
79 
80  if (src[0] & 0x01)
81  src += 5;
82  else
83  src += 2;
84 
85  if (src_end - src < 3)
86  return AVERROR_INVALIDDATA;
87  size = AV_RB24(src);
88  src += 3;
89 
90  while (size > 0 && src < src_end) {
91 
92  /* determine size1 and size2 */
93  size1 = (src[0] & 3);
94  if (src[0] & 0x80) { // 1
95  if (src[0] & 0x40 ) { // 11
96  if (src[0] & 0x20) { // 111
97  if (src[0] < 0xFC) // !(111111)
98  size1 = (((src[0] & 31) + 1) << 2);
99  src++;
100  size2 = 0;
101  } else { // 110
102  offset = ((src[0] & 0x10) << 12) + AV_RB16(&src[1]) + 1;
103  size2 = ((src[0] & 0xC) << 6) + src[3] + 5;
104  src += 4;
105  }
106  } else { // 10
107  size1 = ((src[1] & 0xC0) >> 6);
108  offset = (AV_RB16(&src[1]) & 0x3FFF) + 1;
109  size2 = (src[0] & 0x3F) + 4;
110  src += 3;
111  }
112  } else { // 0
113  offset = ((src[0] & 0x60) << 3) + src[1] + 1;
114  size2 = ((src[0] & 0x1C) >> 2) + 3;
115  src += 2;
116  }
117 
118 
119  /* fetch strip from src */
120  if (size1 > src_end - src)
121  break;
122 
123  if (size1 > 0) {
124  size -= size1;
125  run = FFMIN(size1, dst_end - dst);
126  memcpy(dst, src, run);
127  dst += run;
128  src += run;
129  }
130 
131  if (size2 > 0) {
132  if (dst - dst_start < offset)
133  return 0;
134  size -= size2;
135  run = FFMIN(size2, dst_end - dst);
136  av_memcpy_backptr(dst, offset, run);
137  dst += run;
138  }
139  }
140 
141  return 0;
142 }
143 
144 /**
145  * Decode inter-frame
146  * @return 0 on success, -1 on critical buffer underflow
147  */
149  const uint8_t *buf, const uint8_t *buf_end)
150 {
151  int num_mvs;
152  int num_blocks_raw;
153  int num_blocks_packed;
154  int vector_bits;
155  int i,j,x,y;
156  GetBitContext gb;
157  int mvbits;
158  const uint8_t *blocks_raw;
159 
160  if(buf_end - buf < 12)
161  return AVERROR_INVALIDDATA;
162 
163  num_mvs = AV_RL16(&buf[0]);
164  num_blocks_raw = AV_RL16(&buf[2]);
165  num_blocks_packed = AV_RL16(&buf[4]);
166  vector_bits = AV_RL16(&buf[6]);
167  buf += 12;
168 
169  if (vector_bits > MIN_CACHE_BITS || !vector_bits) {
171  "Invalid value for motion vector bits: %d\n", vector_bits);
172  return AVERROR_INVALIDDATA;
173  }
174 
175  /* allocate codebook buffers as necessary */
176  if (num_mvs > s->num_mvs) {
177  int err = av_reallocp_array(&s->mv_codebook, num_mvs, sizeof(*s->mv_codebook));
178  if (err < 0) {
179  s->num_mvs = 0;
180  return err;
181  }
182  s->num_mvs = num_mvs;
183  }
184 
185  if (num_blocks_packed > s->num_blocks_packed) {
186  int err;
187  if ((err = av_reallocp(&s->block_codebook, num_blocks_packed * 16)) < 0) {
188  s->num_blocks_packed = 0;
189  return err;
190  }
191  s->num_blocks_packed = num_blocks_packed;
192  }
193 
194  /* read motion vectors */
195  mvbits = (num_mvs * 2 * 10 + 31) & ~31;
196 
197  if (buf_end - buf < (mvbits>>3) + 16*num_blocks_raw + 8*num_blocks_packed)
198  return AVERROR_INVALIDDATA;
199 
200  init_get_bits(&gb, buf, mvbits);
201  for (i = 0; i < num_mvs; i++) {
202  s->mv_codebook[i][0] = get_sbits(&gb, 10);
203  s->mv_codebook[i][1] = get_sbits(&gb, 10);
204  }
205  buf += mvbits >> 3;
206 
207  /* note ptr to uncompressed blocks */
208  blocks_raw = buf;
209  buf += num_blocks_raw * 16;
210 
211  /* read compressed blocks */
212  init_get_bits(&gb, buf, (buf_end - buf) << 3);
213  for (i = 0; i < num_blocks_packed; i++) {
214  int tmp[4];
215  for (j = 0; j < 4; j++)
216  tmp[j] = get_bits(&gb, 8);
217  for (j = 0; j < 16; j++)
218  s->block_codebook[i][15-j] = tmp[get_bits(&gb, 2)];
219  }
220 
221  if (get_bits_left(&gb) < vector_bits *
222  (s->avctx->height / 4) * (s->avctx->width / 4))
223  return AVERROR_INVALIDDATA;
224 
225  /* read vectors and build frame */
226  for (y = 0; y < s->avctx->height / 4; y++)
227  for (x = 0; x < s->avctx->width / 4; x++) {
228  unsigned int vector = get_bits(&gb, vector_bits);
229  const uint8_t *src;
230  int src_stride;
231 
232  if (vector < num_mvs) {
233  int mx = x * 4 + s->mv_codebook[vector][0];
234  int my = y * 4 + s->mv_codebook[vector][1];
235 
236  if (mx < 0 || mx + 4 > s->avctx->width ||
237  my < 0 || my + 4 > s->avctx->height) {
238  av_log(s->avctx, AV_LOG_ERROR, "MV %d %d out of picture\n", mx, my);
239  continue;
240  }
241 
242  src = s->last_frame->data[0] + mx + my * s->last_frame->linesize[0];
243  src_stride = s->last_frame->linesize[0];
244  } else {
245  int offset = vector - num_mvs;
246  if (offset < num_blocks_raw)
247  src = blocks_raw + 16*offset;
248  else if (offset - num_blocks_raw < num_blocks_packed)
249  src = s->block_codebook[offset - num_blocks_raw];
250  else
251  continue;
252  src_stride = 4;
253  }
254 
255  for (j = 0; j < 4; j++)
256  for (i = 0; i < 4; i++)
257  frame->data[0][(y * 4 + j) * frame->linesize[0] + (x * 4 + i)] =
258  src[j * src_stride + i];
259  }
260 
261  return 0;
262 }
263 
265  void *data, int *got_frame,
266  AVPacket *avpkt)
267 {
268  const uint8_t *buf = avpkt->data;
269  int buf_size = avpkt->size;
270  TgvContext *s = avctx->priv_data;
271  const uint8_t *buf_end = buf + buf_size;
272  AVFrame *frame = data;
273  int chunk_type, ret;
274 
275  if (buf_end - buf < EA_PREAMBLE_SIZE)
276  return AVERROR_INVALIDDATA;
277 
278  chunk_type = AV_RL32(&buf[0]);
279  buf += EA_PREAMBLE_SIZE;
280 
281  if (chunk_type == kVGT_TAG) {
282  int pal_count, i;
283  if(buf_end - buf < 12) {
284  av_log(avctx, AV_LOG_WARNING, "truncated header\n");
285  return AVERROR_INVALIDDATA;
286  }
287 
288  s->width = AV_RL16(&buf[0]);
289  s->height = AV_RL16(&buf[2]);
290  if (s->avctx->width != s->width || s->avctx->height != s->height) {
291  av_freep(&s->frame_buffer);
293  if ((ret = ff_set_dimensions(s->avctx, s->width, s->height)) < 0)
294  return ret;
295  }
296 
297  pal_count = AV_RL16(&buf[6]);
298  buf += 12;
299  for(i = 0; i < pal_count && i < AVPALETTE_COUNT && buf_end - buf >= 3; i++) {
300  s->palette[i] = 0xFFU << 24 | AV_RB24(buf);
301  buf += 3;
302  }
303  }
304 
305  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
306  return ret;
307 
308  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
309 
310  if (chunk_type == kVGT_TAG) {
311  int y;
312  frame->key_frame = 1;
313  frame->pict_type = AV_PICTURE_TYPE_I;
314 
315  if (!s->frame_buffer &&
316  !(s->frame_buffer = av_mallocz(s->width * s->height)))
317  return AVERROR(ENOMEM);
318 
319  if (unpack(buf, buf_end, s->frame_buffer, s->avctx->width, s->avctx->height) < 0) {
320  av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n");
321  return AVERROR_INVALIDDATA;
322  }
323  for (y = 0; y < s->height; y++)
324  memcpy(frame->data[0] + y * frame->linesize[0],
325  s->frame_buffer + y * s->width,
326  s->width);
327  } else {
328  if (!s->last_frame->data[0]) {
329  av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n");
330  return buf_size;
331  }
332  frame->key_frame = 0;
333  frame->pict_type = AV_PICTURE_TYPE_P;
334  if (tgv_decode_inter(s, frame, buf, buf_end) < 0) {
335  av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n");
336  return AVERROR_INVALIDDATA;
337  }
338  }
339 
341  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
342  return ret;
343 
344  *got_frame = 1;
345 
346  return buf_size;
347 }
348 
350 {
351  TgvContext *s = avctx->priv_data;
353  av_freep(&s->frame_buffer);
354  av_freep(&s->mv_codebook);
356  return 0;
357 }
358 
360  .name = "eatgv",
361  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGV video"),
362  .type = AVMEDIA_TYPE_VIDEO,
363  .id = AV_CODEC_ID_TGV,
364  .priv_data_size = sizeof(TgvContext),
366  .close = tgv_decode_end,
368  .capabilities = AV_CODEC_CAP_DR1,
369 };
int height
Definition: eatgv.c:46
AVRational framerate
Definition: avcodec.h:3374
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVFrame * last_frame
Definition: eatgv.c:44
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:247
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int width
Definition: eatgv.c:46
Memory handling functions.
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:210
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1601
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1903
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:252
uint8_t run
Definition: svq3.c:206
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
AVCodec.
Definition: avcodec.h:3589
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:232
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:141
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:375
#define kVGT_TAG
Definition: eatgv.c:40
AVCodecContext * avctx
Definition: eatgv.c:43
static AVFrame * frame
#define height
uint8_t * data
Definition: avcodec.h:1600
void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
Overlapping memcpy() implementation.
Definition: mem.c:430
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:101
#define av_log(a,...)
int(* mv_codebook)[2]
Definition: eatgv.c:49
#define U(x)
Definition: vp56_arith.h:37
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:568
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
static av_cold int tgv_decode_end(AVCodecContext *avctx)
Definition: eatgv.c:349
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:154
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
int num_mvs
current length of mv_codebook
Definition: eatgv.c:51
const char * name
Name of the codec implementation.
Definition: avcodec.h:3596
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
Definition: mem.c:215
uint32_t palette[AVPALETTE_COUNT]
Definition: eatgv.c:47
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:258
#define FFMIN(a, b)
Definition: common.h:96
uint8_t(* block_codebook)[16]
Definition: eatgv.c:50
#define width
int width
picture width / height.
Definition: avcodec.h:1862
#define src
Definition: vp9dsp.c:530
AVCodec ff_eatgv_decoder
Definition: eatgv.c:359
uint8_t * frame_buffer
Definition: eatgv.c:45
int num_blocks_packed
current length of block_codebook
Definition: eatgv.c:52
#define EA_PREAMBLE_SIZE
Definition: eatgv.c:39
int av_reallocp(void *ptr, size_t size)
Allocate, reallocate, or free a block of memory through a pointer to a pointer.
Definition: mem.c:187
Libavcodec external API header.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
main external API structure.
Definition: avcodec.h:1675
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:934
void * buf
Definition: avisynth_c.h:690
static int tgv_decode_inter(TgvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Decode inter-frame.
Definition: eatgv.c:148
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:406
static av_cold int tgv_decode_init(AVCodecContext *avctx)
Definition: eatgv.c:55
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
#define MIN_CACHE_BITS
Definition: get_bits.h:112
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:485
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
static int unpack(const uint8_t *src, const uint8_t *src_end, uint8_t *dst, int width, int height)
Unpack buffer.
Definition: eatgv.c:73
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:750
common internal api header.
static const int num_mvs[RV34_MB_TYPES]
number of motion vectors in each macroblock type
Definition: rv34.c:851
void * priv_data
Definition: avcodec.h:1717
static uint8_t tmp[8]
Definition: des.c:38
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:253
#define av_freep(p)
static int tgv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eatgv.c:264
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1577
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1353
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:958
Predicted.
Definition: avutil.h:269