Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 
49 static av_cold int decode_end(AVCodecContext *avctx)
50 {
51  C93DecoderContext * const c93 = avctx->priv_data;
52 
53  av_frame_free(&c93->pictures[0]);
54  av_frame_free(&c93->pictures[1]);
55 
56  return 0;
57 }
58 
60 {
61  C93DecoderContext *s = avctx->priv_data;
62  avctx->pix_fmt = AV_PIX_FMT_PAL8;
63 
64  s->pictures[0] = av_frame_alloc();
65  s->pictures[1] = av_frame_alloc();
66  if (!s->pictures[0] || !s->pictures[1]) {
67  decode_end(avctx);
68  return AVERROR(ENOMEM);
69  }
70 
71  return 0;
72 }
73 
74 static inline int copy_block(AVCodecContext *avctx, uint8_t *to,
75  uint8_t *from, int offset, int height, int stride)
76 {
77  int i;
78  int width = height;
79  int from_x = offset % WIDTH;
80  int from_y = offset / WIDTH;
81  int overflow = from_x + width - WIDTH;
82 
83  if (!from) {
84  /* silently ignoring predictive blocks in first frame */
85  return 0;
86  }
87 
88  if (from_y + height > HEIGHT) {
89  av_log(avctx, AV_LOG_ERROR, "invalid offset %d during C93 decoding\n",
90  offset);
91  return AVERROR_INVALIDDATA;
92  }
93 
94  if (overflow > 0) {
95  width -= overflow;
96  for (i = 0; i < height; i++) {
97  memcpy(&to[i*stride+width], &from[(from_y+i)*stride], overflow);
98  }
99  }
100 
101  for (i = 0; i < height; i++) {
102  memcpy(&to[i*stride], &from[(from_y+i)*stride+from_x], width);
103  }
104 
105  return 0;
106 }
107 
108 static inline void draw_n_color(uint8_t *out, int stride, int width,
109  int height, int bpp, uint8_t cols[4], uint8_t grps[4], uint32_t col)
110 {
111  int x, y;
112  for (y = 0; y < height; y++) {
113  if (grps)
114  cols[0] = grps[3 * (y >> 1)];
115  for (x = 0; x < width; x++) {
116  if (grps)
117  cols[1]= grps[(x >> 1) + 1];
118  out[x + y*stride] = cols[col & ((1 << bpp) - 1)];
119  col >>= bpp;
120  }
121  }
122 }
123 
124 static int decode_frame(AVCodecContext *avctx, void *data,
125  int *got_frame, AVPacket *avpkt)
126 {
127  const uint8_t *buf = avpkt->data;
128  int buf_size = avpkt->size;
129  C93DecoderContext * const c93 = avctx->priv_data;
130  AVFrame * const newpic = c93->pictures[c93->currentpic];
131  AVFrame * const oldpic = c93->pictures[c93->currentpic^1];
132  GetByteContext gb;
133  uint8_t *out;
134  int stride, ret, i, x, y, b, bt = 0;
135 
136  c93->currentpic ^= 1;
137 
138  if ((ret = ff_reget_buffer(avctx, newpic)) < 0) {
139  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
140  return ret;
141  }
142 
143  stride = newpic->linesize[0];
144 
145  bytestream2_init(&gb, buf, buf_size);
146  b = bytestream2_get_byte(&gb);
147  if (b & C93_FIRST_FRAME) {
148  newpic->pict_type = AV_PICTURE_TYPE_I;
149  newpic->key_frame = 1;
150  } else {
151  newpic->pict_type = AV_PICTURE_TYPE_P;
152  newpic->key_frame = 0;
153  }
154 
155  for (y = 0; y < HEIGHT; y += 8) {
156  out = newpic->data[0] + y * stride;
157  for (x = 0; x < WIDTH; x += 8) {
158  uint8_t *copy_from = oldpic->data[0];
159  unsigned int offset, j;
160  uint8_t cols[4], grps[4];
161  C93BlockType block_type;
162 
163  if (!bt)
164  bt = bytestream2_get_byte(&gb);
165 
166  block_type= bt & 0x0F;
167  switch (block_type) {
168  case C93_8X8_FROM_PREV:
169  offset = bytestream2_get_le16(&gb);
170  if ((ret = copy_block(avctx, out, copy_from, offset, 8, stride)) < 0)
171  return ret;
172  break;
173 
174  case C93_4X4_FROM_CURR:
175  copy_from = newpic->data[0];
176  case C93_4X4_FROM_PREV:
177  for (j = 0; j < 8; j += 4) {
178  for (i = 0; i < 8; i += 4) {
179  offset = bytestream2_get_le16(&gb);
180  if ((ret = copy_block(avctx, &out[j*stride+i],
181  copy_from, offset, 4, stride)) < 0)
182  return ret;
183  }
184  }
185  break;
186 
187  case C93_8X8_2COLOR:
188  bytestream2_get_buffer(&gb, cols, 2);
189  for (i = 0; i < 8; i++) {
190  draw_n_color(out + i*stride, stride, 8, 1, 1, cols,
191  NULL, bytestream2_get_byte(&gb));
192  }
193 
194  break;
195 
196  case C93_4X4_2COLOR:
197  case C93_4X4_4COLOR:
198  case C93_4X4_4COLOR_GRP:
199  for (j = 0; j < 8; j += 4) {
200  for (i = 0; i < 8; i += 4) {
201  if (block_type == C93_4X4_2COLOR) {
202  bytestream2_get_buffer(&gb, cols, 2);
203  draw_n_color(out + i + j*stride, stride, 4, 4,
204  1, cols, NULL, bytestream2_get_le16(&gb));
205  } else if (block_type == C93_4X4_4COLOR) {
206  bytestream2_get_buffer(&gb, cols, 4);
207  draw_n_color(out + i + j*stride, stride, 4, 4,
208  2, cols, NULL, bytestream2_get_le32(&gb));
209  } else {
210  bytestream2_get_buffer(&gb, grps, 4);
211  draw_n_color(out + i + j*stride, stride, 4, 4,
212  1, cols, grps, bytestream2_get_le16(&gb));
213  }
214  }
215  }
216  break;
217 
218  case C93_NOOP:
219  break;
220 
221  case C93_8X8_INTRA:
222  for (j = 0; j < 8; j++)
223  bytestream2_get_buffer(&gb, out + j*stride, 8);
224  break;
225 
226  default:
227  av_log(avctx, AV_LOG_ERROR, "unexpected type %x at %dx%d\n",
228  block_type, x, y);
229  return AVERROR_INVALIDDATA;
230  }
231  bt >>= 4;
232  out += 8;
233  }
234  }
235 
236  if (b & C93_HAS_PALETTE) {
237  uint32_t *palette = (uint32_t *) newpic->data[1];
238  for (i = 0; i < 256; i++) {
239  palette[i] = bytestream2_get_be24(&gb);
240  }
241  newpic->palette_has_changed = 1;
242  } else {
243  if (oldpic->data[1])
244  memcpy(newpic->data[1], oldpic->data[1], 256 * 4);
245  }
246 
247  if ((ret = av_frame_ref(data, newpic)) < 0)
248  return ret;
249  *got_frame = 1;
250 
251  return buf_size;
252 }
253 
255  .name = "c93",
256  .long_name = NULL_IF_CONFIG_SMALL("Interplay C93"),
257  .type = AVMEDIA_TYPE_VIDEO,
258  .id = AV_CODEC_ID_C93,
259  .priv_data_size = sizeof(C93DecoderContext),
260  .init = decode_init,
261  .close = decode_end,
262  .decode = decode_frame,
263  .capabilities = CODEC_CAP_DR1,
264 };
#define WIDTH
Definition: c93.c:43
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1254
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:130
int stride
Definition: mace.c:144
AVCodec.
Definition: avcodec.h:2796
AVCodec ff_c93_decoder
Definition: c93.c:254
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:108
static av_cold int decode_init(AVCodecContext *avctx)
Definition: c93.c:59
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t
#define av_cold
Definition: attributes.h:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
#define b
Definition: input.c:52
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:188
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: c93.c:124
static av_cold int decode_end(AVCodecContext *avctx)
Definition: c93.c:49
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define C93_HAS_PALETTE
Definition: c93.c:46
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:258
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
#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:808
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
static int copy_from(IpvideoContext *s, AVFrame *src, AVFrame *dst, int delta_x, int delta_y)
NULL
Definition: eval.c:55
static int width
Definition: utils.c:156
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:330
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
int height
Definition: gxfenc.c:72
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){if(!*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));if(!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=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);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);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) 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
common internal api header.
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
void * priv_data
Definition: avcodec.h:1092
C93BlockType
Definition: c93.c:31
static int copy_block(AVCodecContext *avctx, uint8_t *to, uint8_t *from, int offset, int height, int stride)
Definition: c93.c:74
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:191
AVFrame * pictures[2]
Definition: c93.c:27
#define HEIGHT
Definition: c93.c:44
Definition: c93.c:39
This structure stores compressed data.
Definition: avcodec.h:950
int currentpic
Definition: c93.c:28
for(j=16;j >0;--j)
Predicted.
Definition: avutil.h:254