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/mem.h"
32 
33 #define BITSTREAM_READER_LE
34 #include "avcodec.h"
35 #include "get_bits.h"
36 #include "codec_internal.h"
37 #include "decode.h"
38 
39 #define EA_PREAMBLE_SIZE 8
40 #define kVGT_TAG MKTAG('k', 'V', 'G', 'T')
41 
42 typedef struct TgvContext {
45  uint8_t *frame_buffer;
48 
50  uint8_t (*block_codebook)[16];
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 
62  s->last_frame = av_frame_alloc();
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);
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) {
170  av_log(s->avctx, AV_LOG_ERROR,
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  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  int *got_frame, AVPacket *avpkt)
266 {
267  const uint8_t *buf = avpkt->data;
268  int buf_size = avpkt->size;
269  TgvContext *s = avctx->priv_data;
270  const uint8_t *buf_end = buf + buf_size;
271  int chunk_type, ret;
272 
273  if (buf_end - buf < EA_PREAMBLE_SIZE)
274  return AVERROR_INVALIDDATA;
275 
276  chunk_type = AV_RL32(&buf[0]);
277  buf += EA_PREAMBLE_SIZE;
278 
279  if (chunk_type == kVGT_TAG) {
280  int pal_count, i;
281  if(buf_end - buf < 12) {
282  av_log(avctx, AV_LOG_WARNING, "truncated header\n");
283  return AVERROR_INVALIDDATA;
284  }
285 
286  s->width = AV_RL16(&buf[0]);
287  s->height = AV_RL16(&buf[2]);
288  if (s->avctx->width != s->width || s->avctx->height != s->height) {
289  av_freep(&s->frame_buffer);
290  av_frame_unref(s->last_frame);
291  if ((ret = ff_set_dimensions(s->avctx, s->width, s->height)) < 0)
292  return ret;
293  }
294 
295  pal_count = AV_RL16(&buf[6]);
296  buf += 12;
297  for(i = 0; i < pal_count && i < AVPALETTE_COUNT && buf_end - buf >= 3; i++) {
298  s->palette[i] = 0xFFU << 24 | AV_RB24(buf);
299  buf += 3;
300  }
301  if (buf_end - buf < 5) {
302  return AVERROR_INVALIDDATA;
303  }
304  }
305 
306  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
307  return ret;
308 
309  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
310 
311  if (chunk_type == kVGT_TAG) {
312  int y;
315 
316  if (!s->frame_buffer &&
317  !(s->frame_buffer = av_mallocz(s->width * s->height)))
318  return AVERROR(ENOMEM);
319 
320  if (unpack(buf, buf_end, s->frame_buffer, s->avctx->width, s->avctx->height) < 0) {
321  av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n");
322  return AVERROR_INVALIDDATA;
323  }
324  for (y = 0; y < s->height; y++)
325  memcpy(frame->data[0] + y * frame->linesize[0],
326  s->frame_buffer + y * s->width,
327  s->width);
328  } else {
329  if (!s->last_frame->data[0]) {
330  av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n");
331  return buf_size;
332  }
335  if (tgv_decode_inter(s, frame, buf, buf_end) < 0) {
336  av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n");
337  return AVERROR_INVALIDDATA;
338  }
339  }
340 
341  if ((ret = av_frame_replace(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;
352  av_frame_free(&s->last_frame);
353  av_freep(&s->frame_buffer);
354  av_freep(&s->mv_codebook);
355  av_freep(&s->block_codebook);
356  return 0;
357 }
358 
360  .p.name = "eatgv",
361  CODEC_LONG_NAME("Electronic Arts TGV video"),
362  .p.type = AVMEDIA_TYPE_VIDEO,
363  .p.id = AV_CODEC_ID_TGV,
364  .priv_data_size = sizeof(TgvContext),
366  .close = tgv_decode_end,
368  .p.capabilities = AV_CODEC_CAP_DR1,
369 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
tgv_decode_init
static av_cold int tgv_decode_init(AVCodecContext *avctx)
Definition: eatgv.c:55
get_bits_left
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:694
AVERROR
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
num_mvs
static const int num_mvs[RV34_MB_TYPES]
number of motion vectors in each macroblock type
Definition: rv34.c:859
TgvContext::height
int height
Definition: eatgv.c:46
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:100
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
AVPacket::data
uint8_t * data
Definition: packet.h:522
FFCodec
Definition: codec_internal.h:127
TgvContext::num_blocks_packed
int num_blocks_packed
current length of block_codebook
Definition: eatgv.c:52
ff_eatgv_decoder
const FFCodec ff_eatgv_decoder
Definition: eatgv.c:359
AVFrame::flags
int flags
Frame flags, a combination of AV_FRAME_FLAGS.
Definition: frame.h:649
ff_set_dimensions
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:94
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:514
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
TgvContext::avctx
AVCodecContext * avctx
Definition: eatgv.c:43
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:1807
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:335
TgvContext::last_frame
AVFrame * last_frame
Definition: eatgv.c:44
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
GetBitContext
Definition: get_bits.h:108
tgv_decode_frame
static int tgv_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: eatgv.c:264
TgvContext::width
int width
Definition: eatgv.c:46
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:88
TgvContext::num_mvs
int num_mvs
current length of mv_codebook
Definition: eatgv.c:51
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
AV_FRAME_FLAG_KEY
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
Definition: frame.h:628
av_memcpy_backptr
void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
Overlapping memcpy() implementation.
Definition: mem.c:445
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_GET_BUFFER_FLAG_REF
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:425
tgv_decode_inter
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
get_sbits
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:320
decode.h
get_bits.h
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
TgvContext::block_codebook
uint8_t(* block_codebook)[16]
Definition: eatgv.c:50
run
uint8_t run
Definition: svq3.c:203
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:279
AVPALETTE_COUNT
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
kVGT_TAG
#define kVGT_TAG
Definition: eatgv.c:40
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:442
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1618
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:523
codec_internal.h
size
int size
Definition: twinvq_data.h:10344
av_reallocp
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:186
TgvContext::palette
uint32_t palette[AVPALETTE_COUNT]
Definition: eatgv.c:47
EA_PREAMBLE_SIZE
#define EA_PREAMBLE_SIZE
Definition: eatgv.c:39
height
#define height
av_reallocp_array
int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
Allocate, reallocate an array through a pointer to a pointer.
Definition: mem.c:223
offset
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
Definition: writing_filters.txt:86
TgvContext::frame_buffer
uint8_t * frame_buffer
Definition: eatgv.c:45
AV_CODEC_ID_TGV
@ AV_CODEC_ID_TGV
Definition: codec_id.h:172
unpack
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
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:245
MIN_CACHE_BITS
#define MIN_CACHE_BITS
Definition: get_bits.h:169
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:622
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:254
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:662
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
ret
ret
Definition: filter_design.txt:187
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
U
#define U(x)
Definition: vpx_arith.h:37
av_frame_replace
int av_frame_replace(AVFrame *dst, const AVFrame *src)
Ensure the destination frame refers to the same data described by the source frame,...
Definition: frame.c:482
AVCodecContext
main external API structure.
Definition: avcodec.h:445
tgv_decode_end
static av_cold int tgv_decode_end(AVCodecContext *avctx)
Definition: eatgv.c:349
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:280
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
TgvContext::mv_codebook
int(* mv_codebook)[2]
Definition: eatgv.c:49
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:385
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AV_RB24
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:97
int
int
Definition: ffmpeg_filter.c:424
TgvContext
Definition: eatgv.c:42
AV_RB16
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:98