FFmpeg  2.1.1
c93.c
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1 /*
2  * Interplay C93 video decoder
3  * Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
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 #include "avcodec.h"
23 #include "bytestream.h"
24 #include "internal.h"
25 
26 typedef struct {
27  AVFrame pictures[2];
30 
31 typedef enum {
39  C93_NOOP = 0x0E,
40  C93_8X8_INTRA = 0x0F,
41 } C93BlockType;
42 
43 #define WIDTH 320
44 #define HEIGHT 192
45 
46 #define C93_HAS_PALETTE 0x01
47 #define C93_FIRST_FRAME 0x02
48 
50 {
51  C93DecoderContext *s = avctx->priv_data;
52  avctx->pix_fmt = AV_PIX_FMT_PAL8;
55  return 0;
56 }
57 
58 static av_cold int decode_end(AVCodecContext *avctx)
59 {
60  C93DecoderContext * const c93 = avctx->priv_data;
61 
62  av_frame_unref(&c93->pictures[0]);
63  av_frame_unref(&c93->pictures[1]);
64 
65  return 0;
66 }
67 
68 static inline int copy_block(AVCodecContext *avctx, uint8_t *to,
69  uint8_t *from, int offset, int height, int stride)
70 {
71  int i;
72  int width = height;
73  int from_x = offset % WIDTH;
74  int from_y = offset / WIDTH;
75  int overflow = from_x + width - WIDTH;
76 
77  if (!from) {
78  /* silently ignoring predictive blocks in first frame */
79  return 0;
80  }
81 
82  if (from_y + height > HEIGHT) {
83  av_log(avctx, AV_LOG_ERROR, "invalid offset %d during C93 decoding\n",
84  offset);
85  return AVERROR_INVALIDDATA;
86  }
87 
88  if (overflow > 0) {
89  width -= overflow;
90  for (i = 0; i < height; i++) {
91  memcpy(&to[i*stride+width], &from[(from_y+i)*stride], overflow);
92  }
93  }
94 
95  for (i = 0; i < height; i++) {
96  memcpy(&to[i*stride], &from[(from_y+i)*stride+from_x], width);
97  }
98 
99  return 0;
100 }
101 
102 static inline void draw_n_color(uint8_t *out, int stride, int width,
103  int height, int bpp, uint8_t cols[4], uint8_t grps[4], uint32_t col)
104 {
105  int x, y;
106  for (y = 0; y < height; y++) {
107  if (grps)
108  cols[0] = grps[3 * (y >> 1)];
109  for (x = 0; x < width; x++) {
110  if (grps)
111  cols[1]= grps[(x >> 1) + 1];
112  out[x + y*stride] = cols[col & ((1 << bpp) - 1)];
113  col >>= bpp;
114  }
115  }
116 }
117 
118 static int decode_frame(AVCodecContext *avctx, void *data,
119  int *got_frame, AVPacket *avpkt)
120 {
121  const uint8_t *buf = avpkt->data;
122  int buf_size = avpkt->size;
123  C93DecoderContext * const c93 = avctx->priv_data;
124  AVFrame * const newpic = &c93->pictures[c93->currentpic];
125  AVFrame * const oldpic = &c93->pictures[c93->currentpic^1];
126  GetByteContext gb;
127  uint8_t *out;
128  int stride, ret, i, x, y, b, bt = 0;
129 
131 
132  c93->currentpic ^= 1;
133 
134  if ((ret = ff_reget_buffer(avctx, newpic)) < 0)
135  return ret;
136 
137  stride = newpic->linesize[0];
138 
139  bytestream2_init(&gb, buf, buf_size);
140  b = bytestream2_get_byte(&gb);
141  if (b & C93_FIRST_FRAME) {
142  newpic->pict_type = AV_PICTURE_TYPE_I;
143  newpic->key_frame = 1;
144  } else {
145  newpic->pict_type = AV_PICTURE_TYPE_P;
146  newpic->key_frame = 0;
147  }
148 
149  for (y = 0; y < HEIGHT; y += 8) {
150  out = newpic->data[0] + y * stride;
151  for (x = 0; x < WIDTH; x += 8) {
152  uint8_t *copy_from = oldpic->data[0];
153  unsigned int offset, j;
154  uint8_t cols[4], grps[4];
155  C93BlockType block_type;
156 
157  if (!bt)
158  bt = bytestream2_get_byte(&gb);
159 
160  block_type= bt & 0x0F;
161  switch (block_type) {
162  case C93_8X8_FROM_PREV:
163  offset = bytestream2_get_le16(&gb);
164  if ((ret = copy_block(avctx, out, copy_from, offset, 8, stride)) < 0)
165  return ret;
166  break;
167 
168  case C93_4X4_FROM_CURR:
169  copy_from = newpic->data[0];
170  case C93_4X4_FROM_PREV:
171  for (j = 0; j < 8; j += 4) {
172  for (i = 0; i < 8; i += 4) {
173  int offset = bytestream2_get_le16(&gb);
174  int from_x = offset % WIDTH;
175  int from_y = offset / WIDTH;
176  if (block_type == C93_4X4_FROM_CURR && from_y == y+j &&
177  (FFABS(from_x - x-i) < 4 || FFABS(from_x - x-i) > WIDTH-4)) {
178  avpriv_request_sample(avctx, "block overlap %d %d %d %d\n", from_x, x+i, from_y, y+j);
179  return AVERROR_INVALIDDATA;
180  }
181  if ((ret = copy_block(avctx, &out[j*stride+i],
182  copy_from, offset, 4, stride)) < 0)
183  return ret;
184  }
185  }
186  break;
187 
188  case C93_8X8_2COLOR:
189  bytestream2_get_buffer(&gb, cols, 2);
190  for (i = 0; i < 8; i++) {
191  draw_n_color(out + i*stride, stride, 8, 1, 1, cols,
192  NULL, bytestream2_get_byte(&gb));
193  }
194 
195  break;
196 
197  case C93_4X4_2COLOR:
198  case C93_4X4_4COLOR:
199  case C93_4X4_4COLOR_GRP:
200  for (j = 0; j < 8; j += 4) {
201  for (i = 0; i < 8; i += 4) {
202  if (block_type == C93_4X4_2COLOR) {
203  bytestream2_get_buffer(&gb, cols, 2);
204  draw_n_color(out + i + j*stride, stride, 4, 4,
205  1, cols, NULL, bytestream2_get_le16(&gb));
206  } else if (block_type == C93_4X4_4COLOR) {
207  bytestream2_get_buffer(&gb, cols, 4);
208  draw_n_color(out + i + j*stride, stride, 4, 4,
209  2, cols, NULL, bytestream2_get_le32(&gb));
210  } else {
211  bytestream2_get_buffer(&gb, grps, 4);
212  draw_n_color(out + i + j*stride, stride, 4, 4,
213  1, cols, grps, bytestream2_get_le16(&gb));
214  }
215  }
216  }
217  break;
218 
219  case C93_NOOP:
220  break;
221 
222  case C93_8X8_INTRA:
223  for (j = 0; j < 8; j++)
224  bytestream2_get_buffer(&gb, out + j*stride, 8);
225  break;
226 
227  default:
228  av_log(avctx, AV_LOG_ERROR, "unexpected type %x at %dx%d\n",
229  block_type, x, y);
230  return AVERROR_INVALIDDATA;
231  }
232  bt >>= 4;
233  out += 8;
234  }
235  }
236 
237  if (b & C93_HAS_PALETTE) {
238  uint32_t *palette = (uint32_t *) newpic->data[1];
239  for (i = 0; i < 256; i++) {
240  palette[i] = 0xFFU << 24 | bytestream2_get_be24(&gb);
241  }
242  newpic->palette_has_changed = 1;
243  } else {
244  if (oldpic->data[1])
245  memcpy(newpic->data[1], oldpic->data[1], 256 * 4);
246  }
247 
248  if ((ret = av_frame_ref(data, newpic)) < 0)
249  return ret;
250  *got_frame = 1;
251 
252  return buf_size;
253 }
254 
256  .name = "c93",
257  .long_name = NULL_IF_CONFIG_SMALL("Interplay C93"),
258  .type = AVMEDIA_TYPE_VIDEO,
259  .id = AV_CODEC_ID_C93,
260  .priv_data_size = sizeof(C93DecoderContext),
261  .init = decode_init,
262  .close = decode_end,
263  .decode = decode_frame,
264  .capabilities = CODEC_CAP_DR1,
265 };
#define WIDTH
Definition: c93.c:43
const char * s
Definition: avisynth_c.h:668
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
void avcodec_set_dimensions(AVCodecContext *s, int width, int height)
Definition: utils.c:233
int size
Definition: avcodec.h:1064
const char * b
Definition: vf_curves.c:105
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1342
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:131
int stride
Definition: mace.c:144
AVCodec.
Definition: avcodec.h:2922
#define av_cold
Definition: avcodec.h:653
AVCodec ff_c93_decoder
Definition: c93.c:255
static void draw_n_color(uint8_t *out, int stride, int width, int height, int bpp, uint8_t cols[4], uint8_t grps[4], uint32_t col)
Definition: c93.c:102
Predicted.
Definition: avcodec.h:2305
static av_cold int decode_init(AVCodecContext *avctx)
Definition: c93.c:49
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
static const uint8_t offset[511][2]
Definition: vf_uspp.c:58
const char * from
Definition: jacosubdec.c:68
const char * name
Name of the codec implementation.
Definition: avcodec.h:2929
int av_frame_ref(AVFrame *dst, AVFrame *src)
Setup a new reference to the data described by a given frame.
Definition: frame.c:247
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:742
const char data[16]
Definition: mxf.c:68
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: c93.c:118
const char * to
Definition: webvttdec.c:34
static av_cold int decode_end(AVCodecContext *avctx)
Definition: c93.c:58
#define U(x)
Definition: vp56_arith.h:37
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
#define C93_HAS_PALETTE
Definition: c93.c:46
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:261
Libavcodec external API header.
#define C93_FIRST_FRAME
Definition: c93.c:47
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:986
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:167
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:351
float y
ret
Definition: avfilter.c:961
static int copy_from(IpvideoContext *s, AVFrame *src, AVFrame *dst, int delta_x, int delta_y)
static int width
Definition: utils.c:158
main external API structure.
Definition: avcodec.h:1146
AVFrame pictures[2]
Definition: c93.c:27
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:538
void * buf
Definition: avisynth_c.h:594
BYTE int const BYTE int int int height
Definition: avisynth_c.h:713
void avcodec_get_frame_defaults(AVFrame *frame)
Set the fields of the given AVFrame to default values.
Definition: utils.c:1046
uint8_t * data
Definition: avcodec.h:1063
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:303
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:124
#define FFABS(a)
Definition: avcodec.h:920
void * priv_data
Definition: avcodec.h:1182
int palette
Definition: v4l.c:60
common internal api header.
C93BlockType
Definition: c93.c:31
#define AVERROR_INVALIDDATA
static int copy_block(AVCodecContext *avctx, uint8_t *to, uint8_t *from, int offset, int height, int stride)
Definition: c93.c:68
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=av_sample_fmt_is_planar(in_fmt);out_planar=av_sample_fmt_is_planar(out_fmt);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);ff_audio_convert_init_arm(ac);ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> out
int key_frame
1 -&gt; keyframe, 0-&gt; not
Definition: frame.h:162
static int decode(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: crystalhd.c:868
#define HEIGHT
Definition: c93.c:44
8 bit with PIX_FMT_RGB32 palette
Definition: avcodec.h:4545
Definition: c93.c:39
This structure stores compressed data.
Definition: avcodec.h:1040
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:107
int currentpic
Definition: c93.c:28
for(j=16;j >0;--j)