FFmpeg
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 <string.h>
26 
27 #include "libavutil/imgutils.h"
28 #include "libavutil/internal.h"
29 #include "libavutil/intreadwrite.h"
30 
31 #include "avcodec.h"
32 #include "internal.h"
33 
34 typedef struct YopDecContext {
37 
39  int first_color[2];
41 
48 
49 // These tables are taken directly from:
50 // http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP
51 
52 /**
53  * Lookup table for painting macroblocks. Bytes 0-2 of each entry contain
54  * the macroblock positions to be painted (taken as (0, B0, B1, B2)).
55  * Byte 3 contains the number of bytes consumed on the input,
56  * equal to max(bytes 0-2) + 1.
57  */
58 static const uint8_t paint_lut[15][4] =
59  {{1, 2, 3, 4}, {1, 2, 0, 3},
60  {1, 2, 1, 3}, {1, 2, 2, 3},
61  {1, 0, 2, 3}, {1, 0, 0, 2},
62  {1, 0, 1, 2}, {1, 1, 2, 3},
63  {0, 1, 2, 3}, {0, 1, 0, 2},
64  {1, 1, 0, 2}, {0, 1, 1, 2},
65  {0, 0, 1, 2}, {0, 0, 0, 1},
66  {1, 1, 1, 2},
67  };
68 
69 /**
70  * Lookup table for copying macroblocks. Each entry contains the respective
71  * x and y pixel offset for the copy source.
72  */
73 static const int8_t motion_vector[16][2] =
74  {{-4, -4}, {-2, -4},
75  { 0, -4}, { 2, -4},
76  {-4, -2}, {-4, 0},
77  {-3, -3}, {-1, -3},
78  { 1, -3}, { 3, -3},
79  {-3, -1}, {-2, -2},
80  { 0, -2}, { 2, -2},
81  { 4, -2}, {-2, 0},
82  };
83 
85 {
86  YopDecContext *s = avctx->priv_data;
87 
88  av_frame_free(&s->frame);
89 
90  return 0;
91 }
92 
94 {
95  YopDecContext *s = avctx->priv_data;
96  s->avctx = avctx;
97 
98  if (avctx->width & 1 || avctx->height & 1 ||
99  av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
100  av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n");
101  return AVERROR_INVALIDDATA;
102  }
103 
104  if (avctx->extradata_size < 3) {
105  av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata.\n");
106  return AVERROR_INVALIDDATA;
107  }
108 
109  avctx->pix_fmt = AV_PIX_FMT_PAL8;
110 
111  s->num_pal_colors = avctx->extradata[0];
112  s->first_color[0] = avctx->extradata[1];
113  s->first_color[1] = avctx->extradata[2];
114 
115  if (s->num_pal_colors + s->first_color[0] > 256 ||
116  s->num_pal_colors + s->first_color[1] > 256) {
117  av_log(avctx, AV_LOG_ERROR,
118  "Palette parameters invalid, header probably corrupt\n");
119  return AVERROR_INVALIDDATA;
120  }
121 
122  s->frame = av_frame_alloc();
123  if (!s->frame)
124  return AVERROR(ENOMEM);
125 
126  return 0;
127 }
128 
129 /**
130  * Paint a macroblock using the pattern in paint_lut.
131  * @param s codec context
132  * @param tag the tag that was in the nibble
133  */
134 static int yop_paint_block(YopDecContext *s, int linesize, int tag)
135 {
136  if (s->src_end - s->srcptr < paint_lut[tag][3]) {
137  av_log(s->avctx, AV_LOG_ERROR, "Packet too small.\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  s->dstptr[0] = s->srcptr[0];
142  s->dstptr[1] = s->srcptr[paint_lut[tag][0]];
143  s->dstptr[linesize] = s->srcptr[paint_lut[tag][1]];
144  s->dstptr[linesize + 1] = s->srcptr[paint_lut[tag][2]];
145 
146  // The number of src bytes consumed is in the last part of the lut entry.
147  s->srcptr += paint_lut[tag][3];
148  return 0;
149 }
150 
151 /**
152  * Copy a previously painted macroblock to the current_block.
153  * @param copy_tag the tag that was in the nibble
154  */
155 static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
156 {
157  uint8_t *bufptr;
158 
159  // Calculate position for the copy source
160  bufptr = s->dstptr + motion_vector[copy_tag][0] +
161  linesize * motion_vector[copy_tag][1];
162  if (bufptr < s->dstbuf) {
163  av_log(s->avctx, AV_LOG_ERROR, "File probably corrupt\n");
164  return AVERROR_INVALIDDATA;
165  }
166 
167  s->dstptr[0] = bufptr[0];
168  s->dstptr[1] = bufptr[1];
169  s->dstptr[linesize] = bufptr[linesize];
170  s->dstptr[linesize + 1] = bufptr[linesize + 1];
171 
172  return 0;
173 }
174 
175 /**
176  * Return the next nibble in sequence, consuming a new byte on the input
177  * only if necessary.
178  */
180 {
181  int ret;
182 
183  if (s->low_nibble) {
184  ret = *s->low_nibble & 0xf;
185  s->low_nibble = NULL;
186  }else {
187  s->low_nibble = s->srcptr++;
188  ret = *s->low_nibble >> 4;
189  }
190  return ret;
191 }
192 
193 static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
194  AVPacket *avpkt)
195 {
196  YopDecContext *s = avctx->priv_data;
197  AVFrame *frame = s->frame;
198  int tag, firstcolor, is_odd_frame;
199  int ret, i, x, y;
200  uint32_t *palette;
201 
202  if (avpkt->size < 4 + 3 * s->num_pal_colors) {
203  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
204  return AVERROR_INVALIDDATA;
205  }
206 
207  if ((ret = ff_reget_buffer(avctx, frame, 0)) < 0)
208  return ret;
209 
210  if (!avctx->frame_number)
211  memset(frame->data[1], 0, AVPALETTE_SIZE);
212 
213  s->dstbuf = frame->data[0];
214  s->dstptr = frame->data[0];
215  s->srcptr = avpkt->data + 4;
216  s->src_end = avpkt->data + avpkt->size;
217  s->low_nibble = NULL;
218 
219  is_odd_frame = avpkt->data[0];
220  if(is_odd_frame>1){
221  av_log(avctx, AV_LOG_ERROR, "frame is too odd %d\n", is_odd_frame);
222  return AVERROR_INVALIDDATA;
223  }
224  firstcolor = s->first_color[is_odd_frame];
225  palette = (uint32_t *)frame->data[1];
226 
227  for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3) {
228  palette[i + firstcolor] = (s->srcptr[0] << 18) |
229  (s->srcptr[1] << 10) |
230  (s->srcptr[2] << 2);
231  palette[i + firstcolor] |= 0xFFU << 24 |
232  (palette[i + firstcolor] >> 6) & 0x30303;
233  }
234 
235  frame->palette_has_changed = 1;
236 
237  for (y = 0; y < avctx->height; y += 2) {
238  for (x = 0; x < avctx->width; x += 2) {
239  if (s->srcptr - avpkt->data >= avpkt->size) {
240  av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
241  return AVERROR_INVALIDDATA;
242  }
243 
244  tag = yop_get_next_nibble(s);
245 
246  if (tag != 0xf) {
247  ret = yop_paint_block(s, frame->linesize[0], tag);
248  if (ret < 0)
249  return ret;
250  } else {
251  tag = yop_get_next_nibble(s);
252  ret = yop_copy_previous_block(s, frame->linesize[0], tag);
253  if (ret < 0)
254  return ret;
255  }
256  s->dstptr += 2;
257  }
258  s->dstptr += 2*frame->linesize[0] - x;
259  }
260 
261  if ((ret = av_frame_ref(data, s->frame)) < 0)
262  return ret;
263 
264  *got_frame = 1;
265  return avpkt->size;
266 }
267 
269  .name = "yop",
270  .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"),
271  .type = AVMEDIA_TYPE_VIDEO,
272  .id = AV_CODEC_ID_YOP,
273  .priv_data_size = sizeof(YopDecContext),
275  .close = yop_decode_close,
277 };
uint8_t * srcptr
Definition: yop.c:43
static int copy_tag(AVIOContext *in, AVIOContext *out, int32_t tag_name)
Definition: ismindex.c:107
#define NULL
Definition: coverity.c:32
#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:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
misc image utilities
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
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:179
int size
Definition: avcodec.h:1481
uint8_t * src_end
Definition: yop.c:44
int frame_data_length
Definition: yop.c:40
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
AVFrame * frame
Definition: yop.c:36
AVCodec.
Definition: avcodec.h:3484
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
uint8_t * dstptr
Definition: yop.c:45
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
static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: yop.c:193
#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
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1669
uint8_t * data
Definition: avcodec.h:1480
uint32_t tag
Definition: movenc.c:1531
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#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
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 ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:2010
uint8_t * low_nibble
Definition: yop.c:42
static const int8_t motion_vector[16][2]
Lookup table for copying macroblocks.
Definition: yop.c:73
const char * name
Name of the codec implementation.
Definition: avcodec.h:3491
common internal API header
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:282
int width
picture width / height.
Definition: avcodec.h:1741
static const uint8_t paint_lut[15][4]
Lookup table for painting macroblocks.
Definition: yop.c:58
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodec ff_yop_decoder
Definition: yop.c:268
Libavcodec external API header.
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
static av_cold int yop_decode_close(AVCodecContext *avctx)
Definition: yop.c:84
int extradata_size
Definition: avcodec.h:1670
static int yop_paint_block(YopDecContext *s, int linesize, int tag)
Paint a macroblock using the pattern in paint_lut.
Definition: yop.c:134
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:452
int num_pal_colors
Definition: yop.c:38
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
int first_color[2]
Definition: yop.c:39
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:155
common internal api header.
void * priv_data
Definition: avcodec.h:1595
static av_cold int yop_decode_init(AVCodecContext *avctx)
Definition: yop.c:93
#define xf(width, name, var, range_min, range_max, subs,...)
Definition: cbs_av1.c:664
AVCodecContext * avctx
Definition: yop.c:35
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:2259
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
uint8_t * dstbuf
Definition: yop.c:46
This structure stores compressed data.
Definition: avcodec.h:1457
for(j=16;j >0;--j)