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00028 #include "avcodec.h"
00029 #include "get_bits.h"
00030 #include "mathops.h"
00031 #include "dsputil.h"
00032 #include "lagarithrac.h"
00033
00034 enum LagarithFrameType {
00035 FRAME_RAW = 1,
00036 FRAME_U_RGB24 = 2,
00037 FRAME_ARITH_YUY2 = 3,
00038 FRAME_ARITH_RGB24 = 4,
00039 FRAME_SOLID_GRAY = 5,
00040 FRAME_SOLID_COLOR = 6,
00041 FRAME_OLD_ARITH_RGB = 7,
00042 FRAME_ARITH_RGBA = 8,
00043 FRAME_SOLID_RGBA = 9,
00044 FRAME_ARITH_YV12 = 10,
00045 FRAME_REDUCED_RES = 11,
00046 };
00047
00048 typedef struct LagarithContext {
00049 AVCodecContext *avctx;
00050 AVFrame picture;
00051 DSPContext dsp;
00052 int zeros;
00053 int zeros_rem;
00054 uint8_t *rgb_planes;
00055 int rgb_planes_allocated;
00056 int rgb_stride;
00057 } LagarithContext;
00058
00067 static uint64_t softfloat_reciprocal(uint32_t denom)
00068 {
00069 int shift = av_log2(denom - 1) + 1;
00070 uint64_t ret = (1ULL << 52) / denom;
00071 uint64_t err = (1ULL << 52) - ret * denom;
00072 ret <<= shift;
00073 err <<= shift;
00074 err += denom / 2;
00075 return ret + err / denom;
00076 }
00077
00086 static uint32_t softfloat_mul(uint32_t x, uint64_t mantissa)
00087 {
00088 uint64_t l = x * (mantissa & 0xffffffff);
00089 uint64_t h = x * (mantissa >> 32);
00090 h += l >> 32;
00091 l &= 0xffffffff;
00092 l += 1 << av_log2(h >> 21);
00093 h += l >> 32;
00094 return h >> 20;
00095 }
00096
00097 static uint8_t lag_calc_zero_run(int8_t x)
00098 {
00099 return (x << 1) ^ (x >> 7);
00100 }
00101
00102 static int lag_decode_prob(GetBitContext *gb, uint32_t *value)
00103 {
00104 static const uint8_t series[] = { 1, 2, 3, 5, 8, 13, 21 };
00105 int i;
00106 int bit = 0;
00107 int bits = 0;
00108 int prevbit = 0;
00109 unsigned val;
00110
00111 for (i = 0; i < 7; i++) {
00112 if (prevbit && bit)
00113 break;
00114 prevbit = bit;
00115 bit = get_bits1(gb);
00116 if (bit && !prevbit)
00117 bits += series[i];
00118 }
00119 bits--;
00120 if (bits < 0 || bits > 31) {
00121 *value = 0;
00122 return -1;
00123 } else if (bits == 0) {
00124 *value = 0;
00125 return 0;
00126 }
00127
00128 val = get_bits_long(gb, bits);
00129 val |= 1 << bits;
00130
00131 *value = val - 1;
00132
00133 return 0;
00134 }
00135
00136 static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb)
00137 {
00138 int i, j, scale_factor;
00139 unsigned prob, cumulative_target;
00140 unsigned cumul_prob = 0;
00141 unsigned scaled_cumul_prob = 0;
00142
00143 rac->prob[0] = 0;
00144 rac->prob[257] = UINT_MAX;
00145
00146 for (i = 1; i < 257; i++) {
00147 if (lag_decode_prob(gb, &rac->prob[i]) < 0) {
00148 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability encountered.\n");
00149 return -1;
00150 }
00151 if ((uint64_t)cumul_prob + rac->prob[i] > UINT_MAX) {
00152 av_log(rac->avctx, AV_LOG_ERROR, "Integer overflow encountered in cumulative probability calculation.\n");
00153 return -1;
00154 }
00155 cumul_prob += rac->prob[i];
00156 if (!rac->prob[i]) {
00157 if (lag_decode_prob(gb, &prob)) {
00158 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability run encountered.\n");
00159 return -1;
00160 }
00161 if (prob > 257 - i)
00162 prob = 257 - i;
00163 for (j = 0; j < prob; j++)
00164 rac->prob[++i] = 0;
00165 }
00166 }
00167
00168 if (!cumul_prob) {
00169 av_log(rac->avctx, AV_LOG_ERROR, "All probabilities are 0!\n");
00170 return -1;
00171 }
00172
00173
00174 scale_factor = av_log2(cumul_prob);
00175
00176 if (cumul_prob & (cumul_prob - 1)) {
00177 uint64_t mul = softfloat_reciprocal(cumul_prob);
00178 for (i = 1; i < 257; i++) {
00179 rac->prob[i] = softfloat_mul(rac->prob[i], mul);
00180 scaled_cumul_prob += rac->prob[i];
00181 }
00182
00183 scale_factor++;
00184 cumulative_target = 1 << scale_factor;
00185
00186 if (scaled_cumul_prob > cumulative_target) {
00187 av_log(rac->avctx, AV_LOG_ERROR,
00188 "Scaled probabilities are larger than target!\n");
00189 return -1;
00190 }
00191
00192 scaled_cumul_prob = cumulative_target - scaled_cumul_prob;
00193
00194 for (i = 1; scaled_cumul_prob; i = (i & 0x7f) + 1) {
00195 if (rac->prob[i]) {
00196 rac->prob[i]++;
00197 scaled_cumul_prob--;
00198 }
00199
00200
00201
00202
00203
00204
00205
00206
00207
00208
00209
00210 }
00211 }
00212
00213 rac->scale = scale_factor;
00214
00215
00216 for (i = 1; i < 257; i++)
00217 rac->prob[i] += rac->prob[i - 1];
00218
00219 return 0;
00220 }
00221
00222 static void add_lag_median_prediction(uint8_t *dst, uint8_t *src1,
00223 uint8_t *diff, int w, int *left,
00224 int *left_top)
00225 {
00226
00227
00228
00229
00230 int i;
00231 uint8_t l, lt;
00232
00233 l = *left;
00234 lt = *left_top;
00235
00236 for (i = 0; i < w; i++) {
00237 l = mid_pred(l, src1[i], l + src1[i] - lt) + diff[i];
00238 lt = src1[i];
00239 dst[i] = l;
00240 }
00241
00242 *left = l;
00243 *left_top = lt;
00244 }
00245
00246 static void lag_pred_line(LagarithContext *l, uint8_t *buf,
00247 int width, int stride, int line)
00248 {
00249 int L, TL;
00250
00251 if (!line) {
00252
00253 L = l->dsp.add_hfyu_left_prediction(buf + 1, buf + 1,
00254 width - 1, buf[0]);
00255 } else {
00256
00257 L = buf[width - stride - 1];
00258
00259 if (line == 1) {
00260
00261
00262 TL = l->avctx->pix_fmt == PIX_FMT_YUV420P ? buf[-stride] : L;
00263 } else {
00264
00265 TL = buf[width - (2 * stride) - 1];
00266 }
00267
00268 add_lag_median_prediction(buf, buf - stride, buf,
00269 width, &L, &TL);
00270 }
00271 }
00272
00273 static int lag_decode_line(LagarithContext *l, lag_rac *rac,
00274 uint8_t *dst, int width, int stride,
00275 int esc_count)
00276 {
00277 int i = 0;
00278 int ret = 0;
00279
00280 if (!esc_count)
00281 esc_count = -1;
00282
00283
00284 handle_zeros:
00285 if (l->zeros_rem) {
00286 int count = FFMIN(l->zeros_rem, width - i);
00287 memset(dst + i, 0, count);
00288 i += count;
00289 l->zeros_rem -= count;
00290 }
00291
00292 while (i < width) {
00293 dst[i] = lag_get_rac(rac);
00294 ret++;
00295
00296 if (dst[i])
00297 l->zeros = 0;
00298 else
00299 l->zeros++;
00300
00301 i++;
00302 if (l->zeros == esc_count) {
00303 int index = lag_get_rac(rac);
00304 ret++;
00305
00306 l->zeros = 0;
00307
00308 l->zeros_rem = lag_calc_zero_run(index);
00309 goto handle_zeros;
00310 }
00311 }
00312 return ret;
00313 }
00314
00315 static int lag_decode_zero_run_line(LagarithContext *l, uint8_t *dst,
00316 const uint8_t *src, const uint8_t *src_end,
00317 int width, int esc_count)
00318 {
00319 int i = 0;
00320 int count;
00321 uint8_t zero_run = 0;
00322 const uint8_t *src_start = src;
00323 uint8_t mask1 = -(esc_count < 2);
00324 uint8_t mask2 = -(esc_count < 3);
00325 uint8_t *end = dst + (width - 2);
00326
00327 output_zeros:
00328 if (l->zeros_rem) {
00329 count = FFMIN(l->zeros_rem, width - i);
00330 if (end - dst < count) {
00331 av_log(l->avctx, AV_LOG_ERROR, "Too many zeros remaining.\n");
00332 return AVERROR_INVALIDDATA;
00333 }
00334
00335 memset(dst, 0, count);
00336 l->zeros_rem -= count;
00337 dst += count;
00338 }
00339
00340 while (dst < end) {
00341 i = 0;
00342 while (!zero_run && dst + i < end) {
00343 i++;
00344 if (src + i >= src_end)
00345 return AVERROR_INVALIDDATA;
00346 zero_run =
00347 !(src[i] | (src[i + 1] & mask1) | (src[i + 2] & mask2));
00348 }
00349 if (zero_run) {
00350 zero_run = 0;
00351 i += esc_count;
00352 memcpy(dst, src, i);
00353 dst += i;
00354 l->zeros_rem = lag_calc_zero_run(src[i]);
00355
00356 src += i + 1;
00357 goto output_zeros;
00358 } else {
00359 memcpy(dst, src, i);
00360 src += i;
00361 dst += i;
00362 }
00363 }
00364 return src_start - src;
00365 }
00366
00367
00368
00369 static int lag_decode_arith_plane(LagarithContext *l, uint8_t *dst,
00370 int width, int height, int stride,
00371 const uint8_t *src, int src_size)
00372 {
00373 int i = 0;
00374 int read = 0;
00375 uint32_t length;
00376 uint32_t offset = 1;
00377 int esc_count = src[0];
00378 GetBitContext gb;
00379 lag_rac rac;
00380 const uint8_t *src_end = src + src_size;
00381
00382 rac.avctx = l->avctx;
00383 l->zeros = 0;
00384
00385 if (esc_count < 4) {
00386 length = width * height;
00387 if (esc_count && AV_RL32(src + 1) < length) {
00388 length = AV_RL32(src + 1);
00389 offset += 4;
00390 }
00391
00392 init_get_bits(&gb, src + offset, src_size * 8);
00393
00394 if (lag_read_prob_header(&rac, &gb) < 0)
00395 return -1;
00396
00397 lag_rac_init(&rac, &gb, length - stride);
00398
00399 for (i = 0; i < height; i++)
00400 read += lag_decode_line(l, &rac, dst + (i * stride), width,
00401 stride, esc_count);
00402
00403 if (read > length)
00404 av_log(l->avctx, AV_LOG_WARNING,
00405 "Output more bytes than length (%d of %d)\n", read,
00406 length);
00407 } else if (esc_count < 8) {
00408 esc_count -= 4;
00409 if (esc_count > 0) {
00410
00411 for (i = 0; i < height; i++) {
00412 int res = lag_decode_zero_run_line(l, dst + (i * stride), src,
00413 src_end, width, esc_count);
00414 if (res < 0)
00415 return res;
00416 src += res;
00417 }
00418 } else {
00419 if (src_size < width * height)
00420 return AVERROR_INVALIDDATA;
00421
00422 for (i = 0; i < height; i++) {
00423 memcpy(dst + (i * stride), src, width);
00424 src += width;
00425 }
00426 }
00427 } else if (esc_count == 0xff) {
00428
00429 for (i = 0; i < height; i++)
00430 memset(dst + i * stride, src[1], width);
00431
00432
00433
00434 return 0;
00435 } else {
00436 av_log(l->avctx, AV_LOG_ERROR,
00437 "Invalid zero run escape code! (%#x)\n", esc_count);
00438 return -1;
00439 }
00440
00441 for (i = 0; i < height; i++) {
00442 lag_pred_line(l, dst, width, stride, i);
00443 dst += stride;
00444 }
00445
00446 return 0;
00447 }
00448
00457 static int lag_decode_frame(AVCodecContext *avctx,
00458 void *data, int *data_size, AVPacket *avpkt)
00459 {
00460 const uint8_t *buf = avpkt->data;
00461 int buf_size = avpkt->size;
00462 LagarithContext *l = avctx->priv_data;
00463 AVFrame *const p = &l->picture;
00464 uint8_t frametype = 0;
00465 uint32_t offset_gu = 0, offset_bv = 0, offset_ry = 9;
00466 int offs[4];
00467 uint8_t *srcs[4], *dst;
00468 int i, j, planes = 3;
00469
00470 AVFrame *picture = data;
00471
00472 if (p->data[0])
00473 avctx->release_buffer(avctx, p);
00474
00475 p->reference = 0;
00476 p->key_frame = 1;
00477
00478 frametype = buf[0];
00479
00480 offset_gu = AV_RL32(buf + 1);
00481 offset_bv = AV_RL32(buf + 5);
00482
00483 switch (frametype) {
00484 case FRAME_SOLID_RGBA:
00485 avctx->pix_fmt = PIX_FMT_RGB32;
00486
00487 if (avctx->get_buffer(avctx, p) < 0) {
00488 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00489 return -1;
00490 }
00491
00492 dst = p->data[0];
00493 for (j = 0; j < avctx->height; j++) {
00494 for (i = 0; i < avctx->width; i++)
00495 AV_WN32(dst + i * 4, offset_gu);
00496 dst += p->linesize[0];
00497 }
00498 break;
00499 case FRAME_ARITH_RGBA:
00500 avctx->pix_fmt = PIX_FMT_RGB32;
00501 planes = 4;
00502 offset_ry += 4;
00503 offs[3] = AV_RL32(buf + 9);
00504 case FRAME_ARITH_RGB24:
00505 if (frametype == FRAME_ARITH_RGB24)
00506 avctx->pix_fmt = PIX_FMT_RGB24;
00507
00508 if (avctx->get_buffer(avctx, p) < 0) {
00509 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00510 return -1;
00511 }
00512
00513 offs[0] = offset_bv;
00514 offs[1] = offset_gu;
00515 offs[2] = offset_ry;
00516
00517 l->rgb_stride = FFALIGN(avctx->width, 16);
00518 av_fast_malloc(&l->rgb_planes, &l->rgb_planes_allocated,
00519 l->rgb_stride * avctx->height * planes + 1);
00520 if (!l->rgb_planes) {
00521 av_log(avctx, AV_LOG_ERROR, "cannot allocate temporary buffer\n");
00522 return AVERROR(ENOMEM);
00523 }
00524 for (i = 0; i < planes; i++)
00525 srcs[i] = l->rgb_planes + (i + 1) * l->rgb_stride * avctx->height - l->rgb_stride;
00526 if (offset_ry >= buf_size ||
00527 offset_gu >= buf_size ||
00528 offset_bv >= buf_size ||
00529 (planes == 4 && offs[3] >= buf_size)) {
00530 av_log(avctx, AV_LOG_ERROR,
00531 "Invalid frame offsets\n");
00532 return AVERROR_INVALIDDATA;
00533 }
00534 for (i = 0; i < planes; i++)
00535 lag_decode_arith_plane(l, srcs[i],
00536 avctx->width, avctx->height,
00537 -l->rgb_stride, buf + offs[i],
00538 buf_size - offs[i]);
00539 dst = p->data[0];
00540 for (i = 0; i < planes; i++)
00541 srcs[i] = l->rgb_planes + i * l->rgb_stride * avctx->height;
00542 for (j = 0; j < avctx->height; j++) {
00543 for (i = 0; i < avctx->width; i++) {
00544 uint8_t r, g, b, a;
00545 r = srcs[0][i];
00546 g = srcs[1][i];
00547 b = srcs[2][i];
00548 r += g;
00549 b += g;
00550 if (frametype == FRAME_ARITH_RGBA) {
00551 a = srcs[3][i];
00552 AV_WN32(dst + i * 4, MKBETAG(a, r, g, b));
00553 } else {
00554 dst[i * 3 + 0] = r;
00555 dst[i * 3 + 1] = g;
00556 dst[i * 3 + 2] = b;
00557 }
00558 }
00559 dst += p->linesize[0];
00560 for (i = 0; i < planes; i++)
00561 srcs[i] += l->rgb_stride;
00562 }
00563 break;
00564 case FRAME_ARITH_YV12:
00565 avctx->pix_fmt = PIX_FMT_YUV420P;
00566
00567 if (avctx->get_buffer(avctx, p) < 0) {
00568 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00569 return -1;
00570 }
00571
00572 if (offset_ry >= buf_size ||
00573 offset_gu >= buf_size ||
00574 offset_bv >= buf_size) {
00575 av_log(avctx, AV_LOG_ERROR,
00576 "Invalid frame offsets\n");
00577 return AVERROR_INVALIDDATA;
00578 }
00579
00580 lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,
00581 p->linesize[0], buf + offset_ry,
00582 buf_size - offset_ry);
00583 lag_decode_arith_plane(l, p->data[2], avctx->width / 2,
00584 avctx->height / 2, p->linesize[2],
00585 buf + offset_gu, buf_size - offset_gu);
00586 lag_decode_arith_plane(l, p->data[1], avctx->width / 2,
00587 avctx->height / 2, p->linesize[1],
00588 buf + offset_bv, buf_size - offset_bv);
00589 break;
00590 default:
00591 av_log(avctx, AV_LOG_ERROR,
00592 "Unsupported Lagarith frame type: %#x\n", frametype);
00593 return -1;
00594 }
00595
00596 *picture = *p;
00597 *data_size = sizeof(AVFrame);
00598
00599 return buf_size;
00600 }
00601
00602 static av_cold int lag_decode_init(AVCodecContext *avctx)
00603 {
00604 LagarithContext *l = avctx->priv_data;
00605 l->avctx = avctx;
00606
00607 dsputil_init(&l->dsp, avctx);
00608
00609 return 0;
00610 }
00611
00612 static av_cold int lag_decode_end(AVCodecContext *avctx)
00613 {
00614 LagarithContext *l = avctx->priv_data;
00615
00616 if (l->picture.data[0])
00617 avctx->release_buffer(avctx, &l->picture);
00618 av_freep(&l->rgb_planes);
00619
00620 return 0;
00621 }
00622
00623 AVCodec ff_lagarith_decoder = {
00624 .name = "lagarith",
00625 .type = AVMEDIA_TYPE_VIDEO,
00626 .id = CODEC_ID_LAGARITH,
00627 .priv_data_size = sizeof(LagarithContext),
00628 .init = lag_decode_init,
00629 .close = lag_decode_end,
00630 .decode = lag_decode_frame,
00631 .capabilities = CODEC_CAP_DR1,
00632 .long_name = NULL_IF_CONFIG_SMALL("Lagarith lossless"),
00633 };