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 <string.h>
26 
27 #include "libavutil/imgutils.h"
28 #include "libavutil/internal.h"
29 
30 #include "avcodec.h"
31 #include "codec_internal.h"
32 #include "decode.h"
33 
34  typedef struct YopDecContext {
35   AVCodecContext *avctx;
36   AVFrame *frame;
37 
38   int num_pal_colors;
39   int first_color[2];
40   int frame_data_length;
41 
42   const uint8_t *low_nibble;
43   const uint8_t *srcptr;
44   const uint8_t *src_end;
45   uint8_t *dstptr;
46   uint8_t *dstbuf;
47 } YopDecContext;
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 
84  static av_cold int yop_decode_close(AVCodecContext *avctx)
85 {
86  YopDecContext *s = avctx->priv_data;
87 
88  av_frame_free(&s->frame);
89 
90  return 0;
91 }
92 
93  static av_cold int yop_decode_init(AVCodecContext *avctx)
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  */
179  static uint8_t yop_get_next_nibble(YopDecContext *s)
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, AVFrame *rframe,
194  int *got_frame, 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_num)
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  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(rframe, s->frame)) < 0)
260  return ret;
261 
262  *got_frame = 1;
263  return avpkt->size;
264 }
265 
266  const FFCodec ff_yop_decoder = {
267  .p.name = "yop",
268  CODEC_LONG_NAME("Psygnosis YOP Video"),
269  .p.type = AVMEDIA_TYPE_VIDEO,
270  .p.id = AV_CODEC_ID_YOP,
271  .p.capabilities = AV_CODEC_CAP_DR1,
272  .priv_data_size = sizeof(YopDecContext),
273  .init = yop_decode_init,
274  .close = yop_decode_close,
275  FF_CODEC_DECODE_CB(yop_decode_frame),
276 };
YopDecContext::num_pal_colors
int num_pal_colors
Definition: yop.c:38
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
ff_yop_decoder
const FFCodec ff_yop_decoder
Definition: yop.c:266
YopDecContext::src_end
const uint8_t * src_end
Definition: yop.c:44
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:179
YopDecContext::dstbuf
uint8_t * dstbuf
Definition: yop.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:64
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:427
AVPacket::data
uint8_t * data
Definition: packet.h:558
YopDecContext::first_color
int first_color[2]
Definition: yop.c:39
FFCodec
Definition: codec_internal.h:127
AV_CODEC_ID_YOP
@ AV_CODEC_ID_YOP
Definition: codec_id.h:191
paint_lut
static const uint8_t paint_lut[15][4]
Lookup table for painting macroblocks.
Definition: yop.c:58
YopDecContext::avctx
AVCodecContext * avctx
Definition: yop.c:35
close
static av_cold void close(AVCodecParserContext *s)
Definition: apv_parser.c:135
YopDecContext::low_nibble
const uint8_t * low_nibble
Definition: yop.c:42
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:52
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:210
av_cold
#define av_cold
Definition: attributes.h:106
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:515
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:346
s
#define s(width, name)
Definition: cbs_vp9.c:198
YopDecContext::dstptr
uint8_t * dstptr
Definition: yop.c:45
decode.h
motion_vector
static const int8_t motion_vector[16][2]
Lookup table for copying macroblocks.
Definition: yop.c:73
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:331
NULL
#define NULL
Definition: coverity.c:32
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:368
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:559
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:278
codec_internal.h
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:424
YopDecContext::srcptr
const uint8_t * srcptr
Definition: yop.c:43
xf
#define xf(width, name, var, range_min, range_max, subs,...)
Definition: cbs_av1.c:622
yop_decode_close
static av_cold int yop_decode_close(AVCodecContext *avctx)
Definition: yop.c:84
yop_decode_init
static av_cold int yop_decode_init(AVCodecContext *avctx)
Definition: yop.c:93
YopDecContext::frame
AVFrame * frame
Definition: yop.c:36
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVCodecContext::extradata
uint8_t * extradata
Out-of-band global headers that may be used by some codecs.
Definition: avcodec.h:514
internal.h
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:179
AVCodecContext::height
int height
Definition: avcodec.h:592
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:631
YopDecContext
Definition: yop.c:34
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
AVCodecContext::frame_num
int64_t frame_num
Frame counter, set by libavcodec.
Definition: avcodec.h:1878
YopDecContext::frame_data_length
int frame_data_length
Definition: yop.c:40
tag
uint32_t tag
Definition: movenc.c:1957
ff_reget_buffer
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:1840
ret
ret
Definition: filter_design.txt:187
frame
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
Definition: filter_design.txt:265
U
#define U(x)
Definition: vpx_arith.h:37
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:155
AVCodecContext
main external API structure.
Definition: avcodec.h:431
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:200
AVPacket
This structure stores compressed data.
Definition: packet.h:535
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:458
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:134
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:592
imgutils.h
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_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:318
yop_decode_frame
static int yop_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: yop.c:193
copy_tag
static int copy_tag(AVIOContext *in, AVIOContext *out, int32_t tag_name)
Definition: ismindex.c:108
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