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qpeg.c
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1 /*
2  * QPEG codec
3  * Copyright (c) 2004 Konstantin Shishkov
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 /**
23  * @file
24  * QPEG codec.
25  */
26 
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "internal.h"
30 
31 typedef struct QpegContext{
34  uint32_t pal[256];
36 } QpegContext;
37 
38 static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst,
39  int stride, int width, int height)
40 {
41  int i;
42  int code;
43  int c0, c1;
44  int run, copy;
45  int filled = 0;
46  int rows_to_go;
47 
48  rows_to_go = height;
49  height--;
50  dst = dst + height * stride;
51 
52  while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (rows_to_go > 0)) {
53  code = bytestream2_get_byte(&qctx->buffer);
54  run = copy = 0;
55  if(code == 0xFC) /* end-of-picture code */
56  break;
57  if(code >= 0xF8) { /* very long run */
58  c0 = bytestream2_get_byte(&qctx->buffer);
59  c1 = bytestream2_get_byte(&qctx->buffer);
60  run = ((code & 0x7) << 16) + (c0 << 8) + c1 + 2;
61  } else if (code >= 0xF0) { /* long run */
62  c0 = bytestream2_get_byte(&qctx->buffer);
63  run = ((code & 0xF) << 8) + c0 + 2;
64  } else if (code >= 0xE0) { /* short run */
65  run = (code & 0x1F) + 2;
66  } else if (code >= 0xC0) { /* very long copy */
67  c0 = bytestream2_get_byte(&qctx->buffer);
68  c1 = bytestream2_get_byte(&qctx->buffer);
69  copy = ((code & 0x3F) << 16) + (c0 << 8) + c1 + 1;
70  } else if (code >= 0x80) { /* long copy */
71  c0 = bytestream2_get_byte(&qctx->buffer);
72  copy = ((code & 0x7F) << 8) + c0 + 1;
73  } else { /* short copy */
74  copy = code + 1;
75  }
76 
77  /* perform actual run or copy */
78  if(run) {
79  int p;
80 
81  p = bytestream2_get_byte(&qctx->buffer);
82  for(i = 0; i < run; i++) {
83  dst[filled++] = p;
84  if (filled >= width) {
85  filled = 0;
86  dst -= stride;
87  rows_to_go--;
88  if(rows_to_go <= 0)
89  break;
90  }
91  }
92  } else {
93  for(i = 0; i < copy; i++) {
94  dst[filled++] = bytestream2_get_byte(&qctx->buffer);
95  if (filled >= width) {
96  filled = 0;
97  dst -= stride;
98  rows_to_go--;
99  if(rows_to_go <= 0)
100  break;
101  }
102  }
103  }
104  }
105 }
106 
107 static const int qpeg_table_h[16] =
108  { 0x00, 0x20, 0x20, 0x20, 0x18, 0x10, 0x10, 0x20, 0x10, 0x08, 0x18, 0x08, 0x08, 0x18, 0x10, 0x04};
109 static const int qpeg_table_w[16] =
110  { 0x00, 0x20, 0x18, 0x08, 0x18, 0x10, 0x20, 0x10, 0x08, 0x10, 0x20, 0x20, 0x08, 0x10, 0x18, 0x04};
111 
112 /* Decodes delta frames */
114  int stride, int width, int height,
115  int delta, const uint8_t *ctable,
116  uint8_t *refdata)
117 {
118  int i, j;
119  int code;
120  int filled = 0;
121  int orig_height;
122 
123  if (refdata) {
124  /* copy prev frame */
125  for (i = 0; i < height; i++)
126  memcpy(dst + (i * stride), refdata + (i * stride), width);
127  } else {
128  refdata = dst;
129  }
130 
131  orig_height = height;
132  height--;
133  dst = dst + height * stride;
134 
135  while ((bytestream2_get_bytes_left(&qctx->buffer) > 0) && (height >= 0)) {
136  code = bytestream2_get_byte(&qctx->buffer);
137 
138  if(delta) {
139  /* motion compensation */
140  while(bytestream2_get_bytes_left(&qctx->buffer) > 0 && (code & 0xF0) == 0xF0) {
141  if(delta == 1) {
142  int me_idx;
143  int me_w, me_h, me_x, me_y;
144  uint8_t *me_plane;
145  int corr, val;
146 
147  /* get block size by index */
148  me_idx = code & 0xF;
149  me_w = qpeg_table_w[me_idx];
150  me_h = qpeg_table_h[me_idx];
151 
152  /* extract motion vector */
153  corr = bytestream2_get_byte(&qctx->buffer);
154 
155  val = corr >> 4;
156  if(val > 7)
157  val -= 16;
158  me_x = val;
159 
160  val = corr & 0xF;
161  if(val > 7)
162  val -= 16;
163  me_y = val;
164 
165  /* check motion vector */
166  if ((me_x + filled < 0) || (me_x + me_w + filled > width) ||
167  (height - me_y - me_h < 0) || (height - me_y >= orig_height) ||
168  (filled + me_w > width) || (height - me_h < 0))
169  av_log(NULL, AV_LOG_ERROR, "Bogus motion vector (%i,%i), block size %ix%i at %i,%i\n",
170  me_x, me_y, me_w, me_h, filled, height);
171  else {
172  /* do motion compensation */
173  me_plane = refdata + (filled + me_x) + (height - me_y) * stride;
174  for(j = 0; j < me_h; j++) {
175  for(i = 0; i < me_w; i++)
176  dst[filled + i - (j * stride)] = me_plane[i - (j * stride)];
177  }
178  }
179  }
180  code = bytestream2_get_byte(&qctx->buffer);
181  }
182  }
183 
184  if(code == 0xE0) /* end-of-picture code */
185  break;
186  if(code > 0xE0) { /* run code: 0xE1..0xFF */
187  int p;
188 
189  code &= 0x1F;
190  p = bytestream2_get_byte(&qctx->buffer);
191  for(i = 0; i <= code; i++) {
192  dst[filled++] = p;
193  if(filled >= width) {
194  filled = 0;
195  dst -= stride;
196  height--;
197  if (height < 0)
198  break;
199  }
200  }
201  } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */
202  code &= 0x1F;
203 
204  if(code + 1 > bytestream2_get_bytes_left(&qctx->buffer))
205  break;
206 
207  for(i = 0; i <= code; i++) {
208  dst[filled++] = bytestream2_get_byte(&qctx->buffer);
209  if(filled >= width) {
210  filled = 0;
211  dst -= stride;
212  height--;
213  if (height < 0)
214  break;
215  }
216  }
217  } else if(code >= 0x80) { /* skip code: 0x80..0xBF */
218  int skip;
219 
220  code &= 0x3F;
221  /* codes 0x80 and 0x81 are actually escape codes,
222  skip value minus constant is in the next byte */
223  if(!code)
224  skip = bytestream2_get_byte(&qctx->buffer) + 64;
225  else if(code == 1)
226  skip = bytestream2_get_byte(&qctx->buffer) + 320;
227  else
228  skip = code;
229  filled += skip;
230  while( filled >= width) {
231  filled -= width;
232  dst -= stride;
233  height--;
234  if(height < 0)
235  break;
236  }
237  } else {
238  /* zero code treated as one-pixel skip */
239  if(code) {
240  dst[filled++] = ctable[code & 0x7F];
241  }
242  else
243  filled++;
244  if(filled >= width) {
245  filled = 0;
246  dst -= stride;
247  height--;
248  }
249  }
250  }
251 }
252 
253 static int decode_frame(AVCodecContext *avctx,
254  void *data, int *got_frame,
255  AVPacket *avpkt)
256 {
257  uint8_t ctable[128];
258  QpegContext * const a = avctx->priv_data;
259  AVFrame * const p = a->pic;
260  AVFrame * const ref = a->ref;
261  uint8_t* outdata;
262  int delta, ret;
264 
265  if (avpkt->size < 0x86) {
266  av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
267  return AVERROR_INVALIDDATA;
268  }
269 
270  bytestream2_init(&a->buffer, avpkt->data, avpkt->size);
271 
272  av_frame_unref(ref);
273  av_frame_move_ref(ref, p);
274 
275  if ((ret = ff_get_buffer(avctx, p, AV_GET_BUFFER_FLAG_REF)) < 0)
276  return ret;
277  outdata = p->data[0];
278  bytestream2_skip(&a->buffer, 4);
279  bytestream2_get_buffer(&a->buffer, ctable, 128);
280  bytestream2_skip(&a->buffer, 1);
281 
282  delta = bytestream2_get_byte(&a->buffer);
283  if(delta == 0x10) {
284  qpeg_decode_intra(a, outdata, p->linesize[0], avctx->width, avctx->height);
285  } else {
286  qpeg_decode_inter(a, outdata, p->linesize[0], avctx->width, avctx->height, delta, ctable, ref->data[0]);
287  }
288 
289  /* make the palette available on the way out */
290  if (pal) {
291  p->palette_has_changed = 1;
292  memcpy(a->pal, pal, AVPALETTE_SIZE);
293  }
294  memcpy(p->data[1], a->pal, AVPALETTE_SIZE);
295 
296  if ((ret = av_frame_ref(data, p)) < 0)
297  return ret;
298 
299  *got_frame = 1;
300 
301  return avpkt->size;
302 }
303 
304 static void decode_flush(AVCodecContext *avctx){
305  QpegContext * const a = avctx->priv_data;
306  int i, pal_size;
307  const uint8_t *pal_src;
308 
309  pal_size = FFMIN(1024U, avctx->extradata_size);
310  pal_src = avctx->extradata + avctx->extradata_size - pal_size;
311 
312  for (i=0; i<pal_size/4; i++)
313  a->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i);
314 }
315 
317 {
318  QpegContext * const a = avctx->priv_data;
319 
320  av_frame_free(&a->pic);
321  av_frame_free(&a->ref);
322 
323  return 0;
324 }
325 
326 static av_cold int decode_init(AVCodecContext *avctx){
327  QpegContext * const a = avctx->priv_data;
328 
329  a->avctx = avctx;
330  avctx->pix_fmt= AV_PIX_FMT_PAL8;
331 
332  decode_flush(avctx);
333 
334  a->pic = av_frame_alloc();
335  a->ref = av_frame_alloc();
336  if (!a->pic || !a->ref) {
337  decode_end(avctx);
338  return AVERROR(ENOMEM);
339  }
340 
341  return 0;
342 }
343 
345  .name = "qpeg",
346  .long_name = NULL_IF_CONFIG_SMALL("Q-team QPEG"),
347  .type = AVMEDIA_TYPE_VIDEO,
348  .id = AV_CODEC_ID_QPEG,
349  .priv_data_size = sizeof(QpegContext),
350  .init = decode_init,
351  .close = decode_end,
352  .decode = decode_frame,
353  .flush = decode_flush,
354  .capabilities = AV_CODEC_CAP_DR1,
355 };
#define NULL
Definition: coverity.c:32
const char const char void * val
Definition: avisynth_c.h:634
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void flush(AVCodecContext *avctx)
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1424
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1722
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
void av_frame_move_ref(AVFrame *dst, AVFrame *src)
Move everything contained in src to dst and reset src.
Definition: frame.c:484
uint32_t pal[256]
Definition: qpeg.c:34
uint8_t run
Definition: svq3.c:149
AVCodec.
Definition: avcodec.h:3472
uint8_t
#define av_cold
Definition: attributes.h:74
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:135
float delta
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:74
#define AVPALETTE_SIZE
Definition: pixfmt.h:33
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:365
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1617
uint8_t * data
Definition: avcodec.h:1423
static const uint64_t c1
Definition: murmur3.c:49
static void copy(LZOContext *c, int cnt)
Copies bytes from input to output buffer with checking.
Definition: lzo.c:85
static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst, int stride, int width, int height)
Definition: qpeg.c:38
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
static av_cold int decode_init(AVCodecContext *avctx)
Definition: qpeg.c:326
#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_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:148
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:263
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
const char * name
Name of the codec implementation.
Definition: avcodec.h:3479
Libavcodec external API header.
static void decode_flush(AVCodecContext *avctx)
Definition: qpeg.c:304
#define FFMIN(a, b)
Definition: common.h:66
int width
picture width / height.
Definition: avcodec.h:1681
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: qpeg.c:253
AVFrame * pic
Definition: qpeg.c:33
AVCodec ff_qpeg_decoder
Definition: qpeg.c:344
static const int qpeg_table_w[16]
Definition: qpeg.c:109
static const int qpeg_table_h[16]
Definition: qpeg.c:107
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:199
main external API structure.
Definition: avcodec.h:1502
static void av_noinline qpeg_decode_inter(QpegContext *qctx, uint8_t *dst, int stride, int width, int height, int delta, const uint8_t *ctable, uint8_t *refdata)
Definition: qpeg.c:113
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:1040
int extradata_size
Definition: avcodec.h:1618
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:377
GetByteContext buffer
Definition: qpeg.c:35
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:464
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:182
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:523
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
common internal api header.
AVCodecContext * avctx
Definition: qpeg.c:32
static av_cold int decode_end(AVCodecContext *avctx)
Definition: qpeg.c:316
AVFrame * ref
Definition: qpeg.c:33
void * priv_data
Definition: avcodec.h:1544
#define av_noinline
Definition: attributes.h:54
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:324
#define stride
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1400
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1216
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:857
static int width