FFmpeg
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 
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  }
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  ptrdiff_t 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  if (buf_end - buf < 5) {
304  return AVERROR_INVALIDDATA;
305  }
306  }
307 
308  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
309  return ret;
310 
311  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
312 
313  if (chunk_type == kVGT_TAG) {
314  int y;
315  frame->key_frame = 1;
316  frame->pict_type = AV_PICTURE_TYPE_I;
317 
318  if (!s->frame_buffer &&
319  !(s->frame_buffer = av_mallocz(s->width * s->height)))
320  return AVERROR(ENOMEM);
321 
322  if (unpack(buf, buf_end, s->frame_buffer, s->avctx->width, s->avctx->height) < 0) {
323  av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n");
324  return AVERROR_INVALIDDATA;
325  }
326  for (y = 0; y < s->height; y++)
327  memcpy(frame->data[0] + y * frame->linesize[0],
328  s->frame_buffer + y * s->width,
329  s->width);
330  } else {
331  if (!s->last_frame->data[0]) {
332  av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n");
333  return buf_size;
334  }
335  frame->key_frame = 0;
336  frame->pict_type = AV_PICTURE_TYPE_P;
337  if (tgv_decode_inter(s, frame, buf, buf_end) < 0) {
338  av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n");
339  return AVERROR_INVALIDDATA;
340  }
341  }
342 
344  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
345  return ret;
346 
347  *got_frame = 1;
348 
349  return buf_size;
350 }
351 
353 {
354  TgvContext *s = avctx->priv_data;
356  av_freep(&s->frame_buffer);
357  av_freep(&s->mv_codebook);
359  return 0;
360 }
361 
363  .name = "eatgv",
364  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGV video"),
365  .type = AVMEDIA_TYPE_VIDEO,
366  .id = AV_CODEC_ID_TGV,
367  .priv_data_size = sizeof(TgvContext),
369  .close = tgv_decode_end,
371  .capabilities = AV_CODEC_CAP_DR1,
372 };
int height
Definition: eatgv.c:46
AVRational framerate
Definition: avcodec.h:3108
#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:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#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:104
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1481
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
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
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3492
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:359
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
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:189
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
#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:443
#define kVGT_TAG
Definition: eatgv.c:40
AVCodecContext * avctx
Definition: eatgv.c:43
uint8_t * data
Definition: avcodec.h:1480
void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
Overlapping memcpy() implementation.
Definition: mem.c:426
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:100
#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:849
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static av_cold int tgv_decode_end(AVCodecContext *avctx)
Definition: eatgv.c:352
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int num_mvs
current length of mv_codebook
Definition: eatgv.c:51
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
Allocate, reallocate, or free an array through a pointer to a pointer.
Definition: mem.c:205
uint32_t palette[AVPALETTE_COUNT]
Definition: eatgv.c:47
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
#define FFMIN(a, b)
Definition: common.h:96
uint8_t(* block_codebook)[16]
Definition: eatgv.c:50
int width
picture width / height.
Definition: avcodec.h:1741
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodec ff_eatgv_decoder
Definition: eatgv.c:362
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:163
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:326
main external API structure.
Definition: avcodec.h:1568
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
void * buf
Definition: avisynth_c.h:766
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:659
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:128
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
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
int
common internal api header.
void * priv_data
Definition: avcodec.h:1595
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
#define av_freep(p)
static int tgv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eatgv.c:264
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1179
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
Predicted.
Definition: avutil.h:275
static uint8_t tmp[11]
Definition: aes_ctr.c:26