FFmpeg: libavcodec/yop.c Source File

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yop.c
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1 /*
2  * Psygnosis YOP decoder
3  *
4  * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
5  * derived from the code by
6  * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/imgutils.h"
27 
28 #include "avcodec.h"
29 #include "get_bits.h"
30 #include "internal.h"
31 
32  typedef struct YopDecContext {
33   AVCodecContext *avctx;
34   AVFrame *frame;
35 
36   int num_pal_colors;
37   int first_color[2];
38   int frame_data_length;
39 
40   uint8_t *low_nibble;
41   uint8_t *srcptr;
42   uint8_t *src_end;
43   uint8_t *dstptr;
44   uint8_t *dstbuf;
45 } YopDecContext;
46 
47 // These tables are taken directly from:
48 // http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP
49 
50 /**
51  * Lookup table for painting macroblocks. Bytes 0-2 of each entry contain
52  * the macroblock positions to be painted (taken as (0, B0, B1, B2)).
53  * Byte 3 contains the number of bytes consumed on the input,
54  * equal to max(bytes 0-2) + 1.
55  */
56  static const uint8_t paint_lut[15][4] =
57  {{1, 2, 3, 4}, {1, 2, 0, 3},
58  {1, 2, 1, 3}, {1, 2, 2, 3},
59  {1, 0, 2, 3}, {1, 0, 0, 2},
60  {1, 0, 1, 2}, {1, 1, 2, 3},
61  {0, 1, 2, 3}, {0, 1, 0, 2},
62  {1, 1, 0, 2}, {0, 1, 1, 2},
63  {0, 0, 1, 2}, {0, 0, 0, 1},
64  {1, 1, 1, 2},
65  };
66 
67 /**
68  * Lookup table for copying macroblocks. Each entry contains the respective
69  * x and y pixel offset for the copy source.
70  */
71  static const int8_t motion_vector[16][2] =
72  {{-4, -4}, {-2, -4},
73  { 0, -4}, { 2, -4},
74  {-4, -2}, {-4, 0},
75  {-3, -3}, {-1, -3},
76  { 1, -3}, { 3, -3},
77  {-3, -1}, {-2, -2},
78  { 0, -2}, { 2, -2},
79  { 4, -2}, {-2, 0},
80  };
81 
82  static av_cold int yop_decode_close(AVCodecContext *avctx)
83 {
84  YopDecContext *s = avctx->priv_data;
85 
86  av_frame_free(&s->frame);
87 
88  return 0;
89 }
90 
91  static av_cold int yop_decode_init(AVCodecContext *avctx)
92 {
93  YopDecContext *s = avctx->priv_data;
94  s->avctx = avctx;
95 
96  if (avctx->width & 1 || avctx->height & 1 ||
97  av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
98  av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n");
99  return AVERROR_INVALIDDATA;
100  }
101 
102  if (avctx->extradata_size < 3) {
103  av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata.\n");
104  return AVERROR_INVALIDDATA;
105  }
106 
107  avctx->pix_fmt = AV_PIX_FMT_PAL8;
108 
109  s->num_pal_colors = avctx->extradata[0];
110  s->first_color[0] = avctx->extradata[1];
111  s->first_color[1] = avctx->extradata[2];
112 
113  if (s->num_pal_colors + s->first_color[0] > 256 ||
114  s->num_pal_colors + s->first_color[1] > 256) {
115  av_log(avctx, AV_LOG_ERROR,
116  "Palette parameters invalid, header probably corrupt\n");
117  return AVERROR_INVALIDDATA;
118  }
119 
120  s->frame = av_frame_alloc();
121  if (!s->frame)
122  return AVERROR(ENOMEM);
123 
124  return 0;
125 }
126 
127 /**
128  * Paint a macroblock using the pattern in paint_lut.
129  * @param s codec context
130  * @param tag the tag that was in the nibble
131  */
132  static int yop_paint_block(YopDecContext *s, int linesize, int tag)
133 {
134  if (s->src_end - s->srcptr < paint_lut[tag][3]) {
135  av_log(s->avctx, AV_LOG_ERROR, "Packet too small.\n");
136  return AVERROR_INVALIDDATA;
137  }
138 
139  s->dstptr[0] = s->srcptr[0];
140  s->dstptr[1] = s->srcptr[paint_lut[tag][0]];
141  s->dstptr[linesize] = s->srcptr[paint_lut[tag][1]];
142  s->dstptr[linesize + 1] = s->srcptr[paint_lut[tag][2]];
143 
144  // The number of src bytes consumed is in the last part of the lut entry.
145  s->srcptr += paint_lut[tag][3];
146  return 0;
147 }
148 
149 /**
150  * Copy a previously painted macroblock to the current_block.
151  * @param copy_tag the tag that was in the nibble
152  */
153  static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
154 {
155  uint8_t *bufptr;
156 
157  // Calculate position for the copy source
158  bufptr = s->dstptr + motion_vector[copy_tag][0] +
159  linesize * motion_vector[copy_tag][1];
160  if (bufptr < s->dstbuf) {
161  av_log(s->avctx, AV_LOG_ERROR, "File probably corrupt\n");
162  return AVERROR_INVALIDDATA;
163  }
164 
165  s->dstptr[0] = bufptr[0];
166  s->dstptr[1] = bufptr[1];
167  s->dstptr[linesize] = bufptr[linesize];
168  s->dstptr[linesize + 1] = bufptr[linesize + 1];
169 
170  return 0;
171 }
172 
173 /**
174  * Return the next nibble in sequence, consuming a new byte on the input
175  * only if necessary.
176  */
177  static uint8_t yop_get_next_nibble(YopDecContext *s)
178 {
179  int ret;
180 
181  if (s->low_nibble) {
182  ret = *s->low_nibble & 0xf;
183  s->low_nibble = NULL;
184  }else {
185  s->low_nibble = s->srcptr++;
186  ret = *s->low_nibble >> 4;
187  }
188  return ret;
189 }
190 
191  static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
192  AVPacket *avpkt)
193 {
194  YopDecContext *s = avctx->priv_data;
195  AVFrame *frame = s->frame;
196  int tag, firstcolor, is_odd_frame;
197  int ret, i, x, y;
198  uint32_t *palette;
199 
200  if (avpkt->size < 4 + 3 * s->num_pal_colors) {
201  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
202  return AVERROR_INVALIDDATA;
203  }
204 
205  if ((ret = ff_reget_buffer(avctx, frame)) < 0)
206  return ret;
207 
208  if (!avctx->frame_number)
209  memset(frame->data[1], 0, AVPALETTE_SIZE);
210 
211  s->dstbuf = frame->data[0];
212  s->dstptr = frame->data[0];
213  s->srcptr = avpkt->data + 4;
214  s->src_end = avpkt->data + avpkt->size;
215  s->low_nibble = NULL;
216 
217  is_odd_frame = avpkt->data[0];
218  if(is_odd_frame>1){
219  av_log(avctx, AV_LOG_ERROR, "frame is too odd %d\n", is_odd_frame);
220  return AVERROR_INVALIDDATA;
221  }
222  firstcolor = s->first_color[is_odd_frame];
223  palette = (uint32_t *)frame->data[1];
224 
225  for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3) {
226  palette[i + firstcolor] = (s->srcptr[0] << 18) |
227  (s->srcptr[1] << 10) |
228  (s->srcptr[2] << 2);
229  palette[i + firstcolor] |= 0xFFU << 24 |
230  (palette[i + firstcolor] >> 6) & 0x30303;
231  }
232 
233  frame->palette_has_changed = 1;
234 
235  for (y = 0; y < avctx->height; y += 2) {
236  for (x = 0; x < avctx->width; x += 2) {
237  if (s->srcptr - avpkt->data >= avpkt->size) {
238  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
239  return AVERROR_INVALIDDATA;
240  }
241 
242  tag = yop_get_next_nibble(s);
243 
244  if (tag != 0xf) {
245  ret = yop_paint_block(s, frame->linesize[0], tag);
246  if (ret < 0)
247  return ret;
248  } else {
249  tag = yop_get_next_nibble(s);
250  ret = yop_copy_previous_block(s, frame->linesize[0], tag);
251  if (ret < 0)
252  return ret;
253  }
254  s->dstptr += 2;
255  }
256  s->dstptr += 2*frame->linesize[0] - x;
257  }
258 
259  if ((ret = av_frame_ref(data, s->frame)) < 0)
260  return ret;
261 
262  *got_frame = 1;
263  return avpkt->size;
264 }
265 
266  AVCodec ff_yop_decoder = {
267  .name = "yop",
268  .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"),
269  .type = AVMEDIA_TYPE_VIDEO,
270  .id = AV_CODEC_ID_YOP,
271  .priv_data_size = sizeof(YopDecContext),
272  .init = yop_decode_init,
273  .close = yop_decode_close,
274  .decode = yop_decode_frame,
275 };
YopDecContext::srcptr
uint8_t * srcptr
Definition: yop.c:41
copy_tag
static int copy_tag(AVIOContext *in, AVIOContext *out, int32_t tag_name)
Definition: ismindex.c:109
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:631
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:181
data
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
imgutils.h
misc image utilities
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
yop_get_next_nibble
static uint8_t yop_get_next_nibble(YopDecContext *s)
Return the next nibble in sequence, consuming a new byte on the input only if necessary.
Definition: yop.c:177
YopDecContext
Definition: yop.c:32
AVPacket::size
int size
Definition: avcodec.h:1468
YopDecContext::src_end
uint8_t * src_end
Definition: yop.c:42
YopDecContext::frame_data_length
int frame_data_length
Definition: yop.c:38
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1752
YopDecContext::frame
AVFrame * frame
Definition: yop.c:34
AVCodec
AVCodec.
Definition: avcodec.h:3392
YopDecContext::dstptr
uint8_t * dstptr
Definition: yop.c:43
uint8_t
uint8_t
Definition: audio_convert.c:194
av_cold
#define av_cold
Definition: attributes.h:82
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:141
AV_PIX_FMT_PAL8
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:74
yop_decode_frame
static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: yop.c:191
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:33
av_frame_ref
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
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1647
frame
static AVFrame * frame
Definition: demuxing_decoding.c:53
AVPacket::data
uint8_t * data
Definition: avcodec.h:1467
tag
uint32_t tag
Definition: movenc.c:1348
get_bits.h
bitstream reader API header.
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_CODEC_ID_YOP
Definition: avcodec.h:246
U
#define U(x)
Definition: vp56_arith.h:37
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVERROR
#define AVERROR(e)
Definition: error.h:43
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:154
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
YopDecContext::low_nibble
uint8_t * low_nibble
Definition: yop.c:40
motion_vector
static const int8_t motion_vector[16][2]
Lookup table for copying macroblocks.
Definition: yop.c:71
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3399
av_image_check_size
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:251
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: utils.c:943
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1711
paint_lut
static const uint8_t paint_lut[15][4]
Lookup table for painting macroblocks.
Definition: yop.c:56
ff_yop_decoder
AVCodec ff_yop_decoder
Definition: yop.c:266
AVCodecContext::height
int height
Definition: avcodec.h:1711
avcodec.h
Libavcodec external API header.
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:209
AVCodecContext
main external API structure.
Definition: avcodec.h:1532
yop_decode_close
static av_cold int yop_decode_close(AVCodecContext *avctx)
Definition: yop.c:82
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:1648
yop_paint_block
static int yop_paint_block(YopDecContext *s, int linesize, int tag)
Paint a macroblock using the pattern in paint_lut.
Definition: yop.c:132
AVFrame::palette_has_changed
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:322
YopDecContext::num_pal_colors
int num_pal_colors
Definition: yop.c:36
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:192
YopDecContext::first_color
int first_color[2]
Definition: yop.c:37
decode
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:572
palette
int palette
Definition: v4l.c:61
yop_copy_previous_block
static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
Copy a previously painted macroblock to the current_block.
Definition: yop.c:153
internal.h
common internal api header.
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1574
yop_decode_init
static av_cold int yop_decode_init(AVCodecContext *avctx)
Definition: yop.c:91
YopDecContext::avctx
AVCodecContext * avctx
Definition: yop.c:33
AVCodecContext::frame_number
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2318
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:193
YopDecContext::dstbuf
uint8_t * dstbuf
Definition: yop.c:44
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1444
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
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