libavcodec/loco.c

   1 /*
   2  * LOCO codec
   3  * Copyright (c) 2005 Konstantin Shishkov
   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 /**
  23  * @file
  24  * LOCO codec.
  25  */
  26
  27 #include "avcodec.h"
  28 #include "get_bits.h"
  29 #include "golomb.h"
  30 #include "internal.h"
  31 #include "mathops.h"
  32
  33 enum LOCO_MODE {
  34     LOCO_UNKN  =  0,
  35     LOCO_CYUY2 = -1,
  36     LOCO_CRGB  = -2,
  37     LOCO_CRGBA = -3,
  38     LOCO_CYV12 = -4,
  39     LOCO_YUY2  =  1,
  40     LOCO_UYVY  =  2,
  41     LOCO_RGB   =  3,
  42     LOCO_RGBA  =  4,
  43     LOCO_YV12  =  5,
  44 };
  45
  46 typedef struct LOCOContext {
  47     AVCodecContext *avctx;
  48     AVFrame pic;
  49     int lossy;
  50     int mode;
  51 } LOCOContext;
  52
  53 typedef struct RICEContext {
  54     GetBitContext gb;
  55     int save, run, run2; /* internal rice decoder state */
  56     int sum, count; /* sum and count for getting rice parameter */
  57     int lossy;
  58 } RICEContext;
  59
  60 static int loco_get_rice_param(RICEContext *r)
  61 {
  62     int cnt = 0;
  63     int val = r->count;
  64
  65     while (r->sum > val && cnt < 9) {
  66         val <<= 1;
  67         cnt++;
  68     }
  69
  70     return cnt;
  71 }
  72
  73 static inline void loco_update_rice_param(RICEContext *r, int val)
  74 {
  75     r->sum += val;
  76     r->count++;
  77
  78     if (r->count == 16) {
  79         r->sum   >>= 1;
  80         r->count >>= 1;
  81     }
  82 }
  83
  84 static inline int loco_get_rice(RICEContext *r)
  85 {
  86     int v;
  87     if (r->run > 0) { /* we have zero run */
  88         r->run--;
  89         loco_update_rice_param(r, 0);
  90         return 0;
  91     }
  92     v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
  93     loco_update_rice_param(r, (v + 1) >> 1);
  94     if (!v) {
  95         if (r->save >= 0) {
  96             r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
  97             if (r->run > 1)
  98                 r->save += r->run + 1;
  99             else
 100                 r->save -= 3;
 101         } else
 102             r->run2++;
 103     } else {
 104         v = ((v >> 1) + r->lossy) ^ -(v & 1);
 105         if (r->run2 > 0) {
 106             if (r->run2 > 2)
 107                 r->save += r->run2;
 108             else
 109                 r->save -= 3;
 110             r->run2 = 0;
 111         }
 112     }
 113
 114     return v;
 115 }
 116
 117 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
 118 static inline int loco_predict(uint8_t* data, int stride, int step)
 119 {
 120     int a, b, c;
 121
 122     a = data[-stride];
 123     b = data[-step];
 124     c = data[-stride - step];
 125
 126     return mid_pred(a, a + b - c, b);
 127 }
 128
 129 static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
 130                              int stride, const uint8_t *buf, int buf_size, int step)
 131 {
 132     RICEContext rc;
 133     int val;
 134     int i, j;
 135
 136     init_get_bits(&rc.gb, buf, buf_size*8);
 137     rc.save  = 0;
 138     rc.run   = 0;
 139     rc.run2  = 0;
 140     rc.lossy = l->lossy;
 141
 142     rc.sum   = 8;
 143     rc.count = 1;
 144
 145     /* restore top left pixel */
 146     val     = loco_get_rice(&rc);
 147     data[0] = 128 + val;
 148     /* restore top line */
 149     for (i = 1; i < width; i++) {
 150         val = loco_get_rice(&rc);
 151         data[i * step] = data[i * step - step] + val;
 152     }
 153     data += stride;
 154     for (j = 1; j < height; j++) {
 155         /* restore left column */
 156         val = loco_get_rice(&rc);
 157         data[0] = data[-stride] + val;
 158         /* restore all other pixels */
 159         for (i = 1; i < width; i++) {
 160             val = loco_get_rice(&rc);
 161             data[i * step] = loco_predict(&data[i * step], stride, step) + val;
 162         }
 163         data += stride;
 164     }
 165
 166     return (get_bits_count(&rc.gb) + 7) >> 3;
 167 }
 168
 169 static int decode_frame(AVCodecContext *avctx,
 170                         void *data, int *got_frame,
 171                         AVPacket *avpkt)
 172 {
 173     LOCOContext * const l = avctx->priv_data;
 174     const uint8_t *buf    = avpkt->data;
 175     int buf_size          = avpkt->size;
 176     AVFrame * const p     = &l->pic;
 177     int decoded, ret;
 178
 179     if (p->data[0])
 180         avctx->release_buffer(avctx, p);
 181
 182     p->reference = 0;
 183     if ((ret = ff_get_buffer(avctx, p)) < 0) {
 184         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 185         return ret;
 186     }
 187     p->key_frame = 1;
 188
 189     switch(l->mode) {
 190     case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
 191         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 192                                     p->linesize[0], buf, buf_size, 1);
 193         buf += decoded; buf_size -= decoded;
 194         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
 195                                     p->linesize[1], buf, buf_size, 1);
 196         buf += decoded; buf_size -= decoded;
 197         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
 198                                     p->linesize[2], buf, buf_size, 1);
 199         break;
 200     case LOCO_CYV12: case LOCO_YV12:
 201         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 202                                     p->linesize[0], buf, buf_size, 1);
 203         buf += decoded; buf_size -= decoded;
 204         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
 205                                     p->linesize[2], buf, buf_size, 1);
 206         buf += decoded; buf_size -= decoded;
 207         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
 208                                     p->linesize[1], buf, buf_size, 1);
 209         break;
 210     case LOCO_CRGB: case LOCO_RGB:
 211         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
 212                                     -p->linesize[0], buf, buf_size, 3);
 213         buf += decoded; buf_size -= decoded;
 214         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
 215                                     -p->linesize[0], buf, buf_size, 3);
 216         buf += decoded; buf_size -= decoded;
 217         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
 218                                     -p->linesize[0], buf, buf_size, 3);
 219         break;
 220     case LOCO_RGBA:
 221         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
 222                                     p->linesize[0], buf, buf_size, 4);
 223         buf += decoded; buf_size -= decoded;
 224         decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
 225                                     p->linesize[0], buf, buf_size, 4);
 226         buf += decoded; buf_size -= decoded;
 227         decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
 228                                     p->linesize[0], buf, buf_size, 4);
 229         buf += decoded; buf_size -= decoded;
 230         decoded = loco_decode_plane(l, p->data[0] + 3, avctx->width, avctx->height,
 231                                     p->linesize[0], buf, buf_size, 4);
 232         break;
 233     }
 234
 235     *got_frame      = 1;
 236     *(AVFrame*)data = l->pic;
 237
 238     return buf_size;
 239 }
 240
 241 static av_cold int decode_init(AVCodecContext *avctx)
 242 {
 243     LOCOContext * const l = avctx->priv_data;
 244     int version;
 245
 246     l->avctx = avctx;
 247     if (avctx->extradata_size < 12) {
 248         av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
 249                avctx->extradata_size);
 250         return AVERROR_INVALIDDATA;
 251     }
 252     version = AV_RL32(avctx->extradata);
 253     switch (version) {
 254     case 1:
 255         l->lossy = 0;
 256         break;
 257     case 2:
 258         l->lossy = AV_RL32(avctx->extradata + 8);
 259         break;
 260     default:
 261         l->lossy = AV_RL32(avctx->extradata + 8);
 262         av_log_ask_for_sample(avctx, "This is LOCO codec version %i.\n", version);
 263     }
 264
 265     l->mode = AV_RL32(avctx->extradata + 4);
 266     switch (l->mode) {
 267     case LOCO_CYUY2:
 268     case LOCO_YUY2:
 269     case LOCO_UYVY:
 270         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
 271         break;
 272     case LOCO_CRGB:
 273     case LOCO_RGB:
 274         avctx->pix_fmt = AV_PIX_FMT_BGR24;
 275         break;
 276     case LOCO_CYV12:
 277     case LOCO_YV12:
 278         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
 279         break;
 280     case LOCO_CRGBA:
 281     case LOCO_RGBA:
 282         avctx->pix_fmt = AV_PIX_FMT_RGB32;
 283         break;
 284     default:
 285         av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
 286         return AVERROR_INVALIDDATA;
 287     }
 288     if (avctx->debug & FF_DEBUG_PICT_INFO)
 289         av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
 290
 291     return 0;
 292 }
 293
 294 static av_cold int decode_end(AVCodecContext *avctx)
 295 {
 296     LOCOContext * const l = avctx->priv_data;
 297     AVFrame *pic = &l->pic;
 298
 299     if (pic->data[0])
 300         avctx->release_buffer(avctx, pic);
 301
 302     return 0;
 303 }
 304
 305 AVCodec ff_loco_decoder = {
 306     .name           = "loco",
 307     .type           = AVMEDIA_TYPE_VIDEO,
 308     .id             = AV_CODEC_ID_LOCO,
 309     .priv_data_size = sizeof(LOCOContext),
 310     .init           = decode_init,
 311     .close          = decode_end,
 312     .decode         = decode_frame,
 313     .capabilities   = CODEC_CAP_DR1,
 314     .long_name      = NULL_IF_CONFIG_SMALL("LOCO"),
 315 };