/* * Copyright (c) 2012 Konstantin Shishkov * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Common functions for Microsoft Screen 1 and 2 */ #include <inttypes.h> #include "libavutil/intfloat.h" #include "libavutil/intreadwrite.h" #include "avcodec.h" #include "mss12.h" enum SplitMode { SPLIT_VERT = 0, SPLIT_HOR, SPLIT_NONE }; static const int sec_order_sizes[4] = { 1, 7, 6, 1 }; enum ContextDirection { TOP_LEFT = 0, TOP, TOP_RIGHT, LEFT }; static int model_calc_threshold(Model *m) { int thr; thr = 2 * m->weights[m->num_syms] - 1; thr = ((thr >> 1) + 4 * m->cum_prob[0]) / thr; return FFMIN(thr, 0x3FFF); } static void model_reset(Model *m) { int i; for (i = 0; i <= m->num_syms; i++) { m->weights[i] = 1; m->cum_prob[i] = m->num_syms - i; } m->weights[0] = 0; for (i = 0; i < m->num_syms; i++) m->idx2sym[i + 1] = i; } static av_cold void model_init(Model *m, int num_syms, int thr_weight) { m->num_syms = num_syms; m->thr_weight = thr_weight; m->threshold = num_syms * thr_weight; } static void model_rescale_weights(Model *m) { int i; int cum_prob; if (m->thr_weight == THRESH_ADAPTIVE) m->threshold = model_calc_threshold(m); while (m->cum_prob[0] > m->threshold) { cum_prob = 0; for (i = m->num_syms; i >= 0; i--) { m->cum_prob[i] = cum_prob; m->weights[i] = (m->weights[i] + 1) >> 1; cum_prob += m->weights[i]; } } } void ff_mss12_model_update(Model *m, int val) { int i; if (m->weights[val] == m->weights[val - 1]) { for (i = val; m->weights[i - 1] == m->weights[val]; i--); if (i != val) { int sym1, sym2; sym1 = m->idx2sym[val]; sym2 = m->idx2sym[i]; m->idx2sym[val] = sym2; m->idx2sym[i] = sym1; val = i; } } m->weights[val]++; for (i = val - 1; i >= 0; i--) m->cum_prob[i]++; model_rescale_weights(m); } static void pixctx_reset(PixContext *ctx) { int i, j; if (!ctx->special_initial_cache) for (i = 0; i < ctx->cache_size; i++) ctx->cache[i] = i; else { ctx->cache[0] = 1; ctx->cache[1] = 2; ctx->cache[2] = 4; } model_reset(&ctx->cache_model); model_reset(&ctx->full_model); for (i = 0; i < 15; i++) for (j = 0; j < 4; j++) model_reset(&ctx->sec_models[i][j]); } static av_cold void pixctx_init(PixContext *ctx, int cache_size, int full_model_syms, int special_initial_cache) { int i, j, k, idx; ctx->cache_size = cache_size + 4; ctx->num_syms = cache_size; ctx->special_initial_cache = special_initial_cache; model_init(&ctx->cache_model, ctx->num_syms + 1, THRESH_LOW); model_init(&ctx->full_model, full_model_syms, THRESH_HIGH); for (i = 0, idx = 0; i < 4; i++) for (j = 0; j < sec_order_sizes[i]; j++, idx++) for (k = 0; k < 4; k++) model_init(&ctx->sec_models[idx][k], 2 + i, i ? THRESH_LOW : THRESH_ADAPTIVE); } static av_always_inline int decode_pixel(ArithCoder *acoder, PixContext *pctx, uint8_t *ngb, int num_ngb, int any_ngb) { int i, val, pix; if (acoder->overread > MAX_OVERREAD) return AVERROR_INVALIDDATA; val = acoder->get_model_sym(acoder, &pctx->cache_model); if (val < pctx->num_syms) { if (any_ngb) { int idx, j; idx = 0; for (i = 0; i < pctx->cache_size; i++) { for (j = 0; j < num_ngb; j++) if (pctx->cache[i] == ngb[j]) break; if (j == num_ngb) { if (idx == val) break; idx++; } } val = FFMIN(i, pctx->cache_size - 1); } pix = pctx->cache[val]; } else { pix = acoder->get_model_sym(acoder, &pctx->full_model); for (i = 0; i < pctx->cache_size - 1; i++) if (pctx->cache[i] == pix) break; val = i; } if (val) { for (i = val; i > 0; i--) pctx->cache[i] = pctx->cache[i - 1]; pctx->cache[0] = pix; } return pix; } static int decode_pixel_in_context(ArithCoder *acoder, PixContext *pctx, uint8_t *src, ptrdiff_t stride, int x, int y, int has_right) { uint8_t neighbours[4]; uint8_t ref_pix[4]; int nlen; int layer = 0, sub; int pix; int i, j; if (!y) { memset(neighbours, src[-1], 4); } else { neighbours[TOP] = src[-stride]; if (!x) { neighbours[TOP_LEFT] = neighbours[LEFT] = neighbours[TOP]; } else { neighbours[TOP_LEFT] = src[-stride - 1]; neighbours[ LEFT] = src[-1]; } if (has_right) neighbours[TOP_RIGHT] = src[-stride + 1]; else neighbours[TOP_RIGHT] = neighbours[TOP]; } sub = 0; if (x >= 2 && src[-2] == neighbours[LEFT]) sub = 1; if (y >= 2 && src[-2 * stride] == neighbours[TOP]) sub |= 2; nlen = 1; ref_pix[0] = neighbours[0]; for (i = 1; i < 4; i++) { for (j = 0; j < nlen; j++) if (ref_pix[j] == neighbours[i]) break; if (j == nlen) ref_pix[nlen++] = neighbours[i]; } switch (nlen) { case 1: layer = 0; break; case 2: if (neighbours[TOP] == neighbours[TOP_LEFT]) { if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) layer = 1; else if (neighbours[LEFT] == neighbours[TOP_LEFT]) layer = 2; else layer = 3; } else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) { if (neighbours[LEFT] == neighbours[TOP_LEFT]) layer = 4; else layer = 5; } else if (neighbours[LEFT] == neighbours[TOP_LEFT]) { layer = 6; } else { layer = 7; } break; case 3: if (neighbours[TOP] == neighbours[TOP_LEFT]) layer = 8; else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) layer = 9; else if (neighbours[LEFT] == neighbours[TOP_LEFT]) layer = 10; else if (neighbours[TOP_RIGHT] == neighbours[TOP]) layer = 11; else if (neighbours[TOP] == neighbours[LEFT]) layer = 12; else layer = 13; break; case 4: layer = 14; break; } pix = acoder->get_model_sym(acoder, &pctx->sec_models[layer][sub]); if (pix < nlen) return ref_pix[pix]; else return decode_pixel(acoder, pctx, ref_pix, nlen, 1); } static int decode_region(ArithCoder *acoder, uint8_t *dst, uint8_t *rgb_dst, int x, int y, int width, int height, ptrdiff_t stride, ptrdiff_t rgb_stride, PixContext *pctx, const uint32_t *pal) { int i, j, p; rgb_stride = rgb_dst ? rgb_stride : 0; rgb_dst = rgb_dst ? rgb_dst + x * 3 + y * rgb_stride : NULL; dst += x + y * stride; for (j = 0; j < height; j++) { for (i = 0; i < width; i++) { if (!i && !j) p = decode_pixel(acoder, pctx, NULL, 0, 0); else p = decode_pixel_in_context(acoder, pctx, dst + i, stride, i, j, width - i - 1); if (p < 0) return p; dst[i] = p; if (rgb_dst) AV_WB24(rgb_dst + i * 3, pal[p]); } dst += stride; rgb_dst = FF_PTR_ADD(rgb_dst, rgb_stride); } return 0; } static void copy_rectangles(MSS12Context const *c, int x, int y, int width, int height) { int j; if (c->last_rgb_pic) for (j = y; j < y + height; j++) { memcpy(c->rgb_pic + j * c->rgb_stride + x * 3, c->last_rgb_pic + j * c->rgb_stride + x * 3, width * 3); memcpy(c->pal_pic + j * c->pal_stride + x, c->last_pal_pic + j * c->pal_stride + x, width); } } static int motion_compensation(MSS12Context const *c, int x, int y, int width, int height) { if (x + c->mvX < 0 || x + c->mvX + width > c->avctx->width || y + c->mvY < 0 || y + c->mvY + height > c->avctx->height || !c->rgb_pic) return -1; else { uint8_t *dst = c->pal_pic + x + y * c->pal_stride; uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride; uint8_t *src; uint8_t *rgb_src; int j; x += c->mvX; y += c->mvY; if (c->last_rgb_pic) { src = c->last_pal_pic + x + y * c->pal_stride; rgb_src = c->last_rgb_pic + x * 3 + y * c->rgb_stride; } else { src = c->pal_pic + x + y * c->pal_stride; rgb_src = c->rgb_pic + x * 3 + y * c->rgb_stride; } for (j = 0; j < height; j++) { memmove(dst, src, width); memmove(rgb_dst, rgb_src, width * 3); dst += c->pal_stride; src += c->pal_stride; rgb_dst += c->rgb_stride; rgb_src += c->rgb_stride; } } return 0; } static int decode_region_masked(MSS12Context const *c, ArithCoder *acoder, uint8_t *dst, ptrdiff_t stride, uint8_t *mask, ptrdiff_t mask_stride, int x, int y, int width, int height, PixContext *pctx) { int i, j, p; uint8_t *rgb_dst = c->rgb_pic + x * 3 + y * c->rgb_stride; dst += x + y * stride; mask += x + y * mask_stride; for (j = 0; j < height; j++) { for (i = 0; i < width; i++) { if (c->avctx->err_recognition & AV_EF_EXPLODE && ( c->rgb_pic && mask[i] != 0x01 && mask[i] != 0x02 && mask[i] != 0x04 || !c->rgb_pic && mask[i] != 0x80 && mask[i] != 0xFF)) return -1; if (mask[i] == 0x02) { copy_rectangles(c, x + i, y + j, 1, 1); } else if (mask[i] == 0x04) { if (motion_compensation(c, x + i, y + j, 1, 1)) return -1; } else if (mask[i] != 0x80) { if (!i && !j) p = decode_pixel(acoder, pctx, NULL, 0, 0); else p = decode_pixel_in_context(acoder, pctx, dst + i, stride, i, j, width - i - 1); if (p < 0) return p; dst[i] = p; if (c->rgb_pic) AV_WB24(rgb_dst + i * 3, c->pal[p]); } } dst += stride; mask += mask_stride; rgb_dst += c->rgb_stride; } return 0; } static av_cold void slicecontext_init(SliceContext *sc, int version, int full_model_syms) { model_init(&sc->intra_region, 2, THRESH_ADAPTIVE); model_init(&sc->inter_region, 2, THRESH_ADAPTIVE); model_init(&sc->split_mode, 3, THRESH_HIGH); model_init(&sc->edge_mode, 2, THRESH_HIGH); model_init(&sc->pivot, 3, THRESH_LOW); pixctx_init(&sc->intra_pix_ctx, 8, full_model_syms, 0); pixctx_init(&sc->inter_pix_ctx, version ? 3 : 2, full_model_syms, version ? 1 : 0); } void ff_mss12_slicecontext_reset(SliceContext *sc) { model_reset(&sc->intra_region); model_reset(&sc->inter_region); model_reset(&sc->split_mode); model_reset(&sc->edge_mode); model_reset(&sc->pivot); pixctx_reset(&sc->intra_pix_ctx); pixctx_reset(&sc->inter_pix_ctx); } static int decode_pivot(SliceContext *sc, ArithCoder *acoder, int base) { int val, inv; inv = acoder->get_model_sym(acoder, &sc->edge_mode); val = acoder->get_model_sym(acoder, &sc->pivot) + 1; if (val > 2) { if ((base + 1) / 2 - 2 <= 0) return -1; val = acoder->get_number(acoder, (base + 1) / 2 - 2) + 3; } if ((unsigned)val >= base) return -1; return inv ? base - val : val; } static int decode_region_intra(SliceContext *sc, ArithCoder *acoder, int x, int y, int width, int height) { MSS12Context const *c = sc->c; int mode; mode = acoder->get_model_sym(acoder, &sc->intra_region); if (!mode) { int i, j, pix, rgb_pix; ptrdiff_t stride = c->pal_stride; ptrdiff_t rgb_stride = c->rgb_stride; uint8_t *dst = c->pal_pic + x + y * stride; uint8_t *rgb_dst = c->rgb_pic ? c->rgb_pic + x * 3 + y * rgb_stride : NULL; pix = decode_pixel(acoder, &sc->intra_pix_ctx, NULL, 0, 0); if (pix < 0) return pix; rgb_pix = c->pal[pix]; for (i = 0; i < height; i++, dst += stride) { memset(dst, pix, width); if (rgb_dst) { for (j = 0; j < width * 3; j += 3) AV_WB24(rgb_dst + j, rgb_pix); rgb_dst += rgb_stride; } } } else { return decode_region(acoder, c->pal_pic, c->rgb_pic, x, y, width, height, c->pal_stride, c->rgb_stride, &sc->intra_pix_ctx, &c->pal[0]); } return 0; } static int decode_region_inter(SliceContext *sc, ArithCoder *acoder, int x, int y, int width, int height) { MSS12Context const *c = sc->c; int mode; mode = acoder->get_model_sym(acoder, &sc->inter_region); if (!mode) { mode = decode_pixel(acoder, &sc->inter_pix_ctx, NULL, 0, 0); if (mode < 0) return mode; if (c->avctx->err_recognition & AV_EF_EXPLODE && ( c->rgb_pic && mode != 0x01 && mode != 0x02 && mode != 0x04 || !c->rgb_pic && mode != 0x80 && mode != 0xFF)) return -1; if (mode == 0x02) copy_rectangles(c, x, y, width, height); else if (mode == 0x04) return motion_compensation(c, x, y, width, height); else if (mode != 0x80) return decode_region_intra(sc, acoder, x, y, width, height); } else { if (decode_region(acoder, c->mask, NULL, x, y, width, height, c->mask_stride, 0, &sc->inter_pix_ctx, &c->pal[0]) < 0) return -1; return decode_region_masked(c, acoder, c->pal_pic, c->pal_stride, c->mask, c->mask_stride, x, y, width, height, &sc->intra_pix_ctx); } return 0; } int ff_mss12_decode_rect(SliceContext *sc, ArithCoder *acoder, int x, int y, int width, int height) { int mode, pivot; if (acoder->overread > MAX_OVERREAD) return AVERROR_INVALIDDATA; mode = acoder->get_model_sym(acoder, &sc->split_mode); switch (mode) { case SPLIT_VERT: if ((pivot = decode_pivot(sc, acoder, height)) < 1) return -1; if (ff_mss12_decode_rect(sc, acoder, x, y, width, pivot)) return -1; if (ff_mss12_decode_rect(sc, acoder, x, y + pivot, width, height - pivot)) return -1; break; case SPLIT_HOR: if ((pivot = decode_pivot(sc, acoder, width)) < 1) return -1; if (ff_mss12_decode_rect(sc, acoder, x, y, pivot, height)) return -1; if (ff_mss12_decode_rect(sc, acoder, x + pivot, y, width - pivot, height)) return -1; break; case SPLIT_NONE: if (sc->c->keyframe) return decode_region_intra(sc, acoder, x, y, width, height); else return decode_region_inter(sc, acoder, x, y, width, height); default: return -1; } return 0; } av_cold int ff_mss12_decode_init(MSS12Context *c, int version, SliceContext* sc1, SliceContext *sc2) { AVCodecContext *avctx = c->avctx; int i; if (avctx->extradata_size < 52 + 256 * 3) { av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d\n", avctx->extradata_size); return AVERROR_INVALIDDATA; } if (AV_RB32(avctx->extradata) < avctx->extradata_size) { av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size: expected %"PRIu32" got %d\n", AV_RB32(avctx->extradata), avctx->extradata_size); return AVERROR_INVALIDDATA; } avctx->coded_width = FFMAX(AV_RB32(avctx->extradata + 20), avctx->width); avctx->coded_height = FFMAX(AV_RB32(avctx->extradata + 24), avctx->height); if (avctx->coded_width > 4096 || avctx->coded_height > 4096) { av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too large", avctx->coded_width, avctx->coded_height); return AVERROR_INVALIDDATA; } if (avctx->coded_width < 1 || avctx->coded_height < 1) { av_log(avctx, AV_LOG_ERROR, "Frame dimensions %dx%d too small", avctx->coded_width, avctx->coded_height); return AVERROR_INVALIDDATA; } av_log(avctx, AV_LOG_DEBUG, "Encoder version %"PRIu32".%"PRIu32"\n", AV_RB32(avctx->extradata + 4), AV_RB32(avctx->extradata + 8)); if (version != AV_RB32(avctx->extradata + 4) > 1) { av_log(avctx, AV_LOG_ERROR, "Header version doesn't match codec tag\n"); return -1; } c->free_colours = AV_RB32(avctx->extradata + 48); if ((unsigned)c->free_colours > 256) { av_log(avctx, AV_LOG_ERROR, "Incorrect number of changeable palette entries: %d\n", c->free_colours); return AVERROR_INVALIDDATA; } av_log(avctx, AV_LOG_DEBUG, "%d free colour(s)\n", c->free_colours); av_log(avctx, AV_LOG_DEBUG, "Display dimensions %"PRIu32"x%"PRIu32"\n", AV_RB32(avctx->extradata + 12), AV_RB32(avctx->extradata + 16)); av_log(avctx, AV_LOG_DEBUG, "Coded dimensions %dx%d\n", avctx->coded_width, avctx->coded_height); av_log(avctx, AV_LOG_DEBUG, "%g frames per second\n", av_int2float(AV_RB32(avctx->extradata + 28))); av_log(avctx, AV_LOG_DEBUG, "Bitrate %"PRIu32" bps\n", AV_RB32(avctx->extradata + 32)); av_log(avctx, AV_LOG_DEBUG, "Max. lead time %g ms\n", av_int2float(AV_RB32(avctx->extradata + 36))); av_log(avctx, AV_LOG_DEBUG, "Max. lag time %g ms\n", av_int2float(AV_RB32(avctx->extradata + 40))); av_log(avctx, AV_LOG_DEBUG, "Max. seek time %g ms\n", av_int2float(AV_RB32(avctx->extradata + 44))); if (version) { if (avctx->extradata_size < 60 + 256 * 3) { av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d for v2\n", avctx->extradata_size); return AVERROR_INVALIDDATA; } c->slice_split = AV_RB32(avctx->extradata + 52); av_log(avctx, AV_LOG_DEBUG, "Slice split %d\n", c->slice_split); c->full_model_syms = AV_RB32(avctx->extradata + 56); if (c->full_model_syms < 2 || c->full_model_syms > 256) { av_log(avctx, AV_LOG_ERROR, "Incorrect number of used colours %d\n", c->full_model_syms); return AVERROR_INVALIDDATA; } av_log(avctx, AV_LOG_DEBUG, "Used colours %d\n", c->full_model_syms); } else { c->slice_split = 0; c->full_model_syms = 256; } for (i = 0; i < 256; i++) c->pal[i] = 0xFFU << 24 | AV_RB24(avctx->extradata + 52 + (version ? 8 : 0) + i * 3); c->mask_stride = FFALIGN(avctx->width, 16); c->mask = av_malloc_array(c->mask_stride, avctx->height); if (!c->mask) { av_log(avctx, AV_LOG_ERROR, "Cannot allocate mask plane\n"); return AVERROR(ENOMEM); } sc1->c = c; slicecontext_init(sc1, version, c->full_model_syms); if (c->slice_split) { sc2->c = c; slicecontext_init(sc2, version, c->full_model_syms); } c->corrupted = 1; return 0; } av_cold int ff_mss12_decode_end(MSS12Context *c) { av_freep(&c->mask); return 0; }