yading@10: /* yading@10: * Microsoft Screen 4 (aka Microsoft Expression Encoder Screen) decoder yading@10: * Copyright (c) 2012 Konstantin Shishkov yading@10: * yading@10: * This file is part of FFmpeg. yading@10: * yading@10: * FFmpeg is free software; you can redistribute it and/or yading@10: * modify it under the terms of the GNU Lesser General Public yading@10: * License as published by the Free Software Foundation; either yading@10: * version 2.1 of the License, or (at your option) any later version. yading@10: * yading@10: * FFmpeg is distributed in the hope that it will be useful, yading@10: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@10: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@10: * Lesser General Public License for more details. yading@10: * yading@10: * You should have received a copy of the GNU Lesser General Public yading@10: * License along with FFmpeg; if not, write to the Free Software yading@10: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@10: */ yading@10: yading@10: /** yading@10: * @file yading@10: * Microsoft Screen 4 (aka Microsoft Titanium Screen 2, yading@10: * aka Microsoft Expression Encoder Screen) decoder yading@10: */ yading@10: yading@10: #include "avcodec.h" yading@10: #include "bytestream.h" yading@10: #include "dsputil.h" yading@10: #include "get_bits.h" yading@10: #include "internal.h" yading@10: #include "mss34dsp.h" yading@10: #include "unary.h" yading@10: yading@10: #define HEADER_SIZE 8 yading@10: yading@10: enum FrameType { yading@10: INTRA_FRAME = 0, yading@10: INTER_FRAME, yading@10: SKIP_FRAME yading@10: }; yading@10: yading@10: enum BlockType { yading@10: SKIP_BLOCK = 0, yading@10: DCT_BLOCK, yading@10: IMAGE_BLOCK, yading@10: }; yading@10: yading@10: enum CachePos { yading@10: LEFT = 0, yading@10: TOP_LEFT, yading@10: TOP, yading@10: }; yading@10: yading@10: static const uint8_t mss4_dc_vlc_lens[2][16] = { yading@10: { 0, 1, 5, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0 }, yading@10: { 0, 3, 1, 1, 1, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0 } yading@10: }; yading@10: yading@10: static const uint8_t mss4_ac_vlc_lens[2][16] = { yading@10: { 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 125 }, yading@10: { 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 119 } yading@10: }; yading@10: yading@10: static const uint8_t mss4_ac_vlc_syms[2][162] = { yading@10: { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, yading@10: 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, yading@10: 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xA1, 0x08, yading@10: 0x23, 0x42, 0xB1, 0xC1, 0x15, 0x52, 0xD1, 0xF0, yading@10: 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0A, 0x16, yading@10: 0x17, 0x18, 0x19, 0x1A, 0x25, 0x26, 0x27, 0x28, yading@10: 0x29, 0x2A, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, yading@10: 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, yading@10: 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, yading@10: 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, yading@10: 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, yading@10: 0x7A, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, yading@10: 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, yading@10: 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, yading@10: 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, yading@10: 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5, yading@10: 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3, 0xD4, yading@10: 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xE1, 0xE2, yading@10: 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, yading@10: 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, yading@10: 0xF9, 0xFA }, yading@10: { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, yading@10: 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, yading@10: 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, yading@10: 0xA1, 0xB1, 0xC1, 0x09, 0x23, 0x33, 0x52, 0xF0, yading@10: 0x15, 0x62, 0x72, 0xD1, 0x0A, 0x16, 0x24, 0x34, yading@10: 0xE1, 0x25, 0xF1, 0x17, 0x18, 0x19, 0x1A, 0x26, yading@10: 0x27, 0x28, 0x29, 0x2A, 0x35, 0x36, 0x37, 0x38, yading@10: 0x39, 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, yading@10: 0x49, 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, yading@10: 0x59, 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, yading@10: 0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, yading@10: 0x79, 0x7A, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, yading@10: 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, yading@10: 0x97, 0x98, 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, yading@10: 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, yading@10: 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, yading@10: 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, yading@10: 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, yading@10: 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, yading@10: 0xEA, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, yading@10: 0xF9, 0xFA } yading@10: }; yading@10: yading@10: static const uint8_t vec_len_syms[2][4] = { yading@10: { 4, 2, 3, 1 }, yading@10: { 4, 1, 2, 3 } yading@10: }; yading@10: yading@10: static const uint8_t mss4_vec_entry_vlc_lens[2][16] = { yading@10: { 0, 2, 2, 3, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, yading@10: { 0, 1, 5, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } yading@10: }; yading@10: yading@10: static const uint8_t mss4_vec_entry_vlc_syms[2][9] = { yading@10: { 0, 7, 6, 5, 8, 4, 3, 1, 2 }, yading@10: { 0, 2, 3, 4, 5, 6, 7, 1, 8 } yading@10: }; yading@10: yading@10: #define MAX_ENTRIES 162 yading@10: yading@10: typedef struct MSS4Context { yading@10: AVFrame *pic; yading@10: yading@10: VLC dc_vlc[2], ac_vlc[2]; yading@10: VLC vec_entry_vlc[2]; yading@10: int block[64]; yading@10: uint8_t imgbuf[3][16 * 16]; yading@10: yading@10: int quality; yading@10: uint16_t quant_mat[2][64]; yading@10: yading@10: int *prev_dc[3]; yading@10: int dc_stride[3]; yading@10: int dc_cache[4][4]; yading@10: yading@10: int prev_vec[3][4]; yading@10: } MSS4Context; yading@10: yading@10: static av_cold int mss4_init_vlc(VLC *vlc, const uint8_t *lens, yading@10: const uint8_t *syms, int num_syms) yading@10: { yading@10: uint8_t bits[MAX_ENTRIES]; yading@10: uint16_t codes[MAX_ENTRIES]; yading@10: int i, j; yading@10: int prefix = 0, max_bits = 0, idx = 0; yading@10: yading@10: for (i = 0; i < 16; i++) { yading@10: for (j = 0; j < lens[i]; j++) { yading@10: bits[idx] = i + 1; yading@10: codes[idx] = prefix++; yading@10: max_bits = i + 1; yading@10: idx++; yading@10: } yading@10: prefix <<= 1; yading@10: } yading@10: yading@10: return ff_init_vlc_sparse(vlc, FFMIN(max_bits, 9), num_syms, bits, 1, 1, yading@10: codes, 2, 2, syms, 1, 1, 0); yading@10: } yading@10: yading@10: static av_cold int mss4_init_vlcs(MSS4Context *ctx) yading@10: { yading@10: int ret, i; yading@10: yading@10: for (i = 0; i < 2; i++) { yading@10: ret = mss4_init_vlc(&ctx->dc_vlc[i], mss4_dc_vlc_lens[i], NULL, 12); yading@10: if (ret) yading@10: return ret; yading@10: ret = mss4_init_vlc(&ctx->ac_vlc[i], mss4_ac_vlc_lens[i], yading@10: mss4_ac_vlc_syms[i], 162); yading@10: if (ret) yading@10: return ret; yading@10: ret = mss4_init_vlc(&ctx->vec_entry_vlc[i], mss4_vec_entry_vlc_lens[i], yading@10: mss4_vec_entry_vlc_syms[i], 9); yading@10: if (ret) yading@10: return ret; yading@10: } yading@10: return 0; yading@10: } yading@10: yading@10: static av_cold void mss4_free_vlcs(MSS4Context *ctx) yading@10: { yading@10: int i; yading@10: yading@10: for (i = 0; i < 2; i++) { yading@10: ff_free_vlc(&ctx->dc_vlc[i]); yading@10: ff_free_vlc(&ctx->ac_vlc[i]); yading@10: ff_free_vlc(&ctx->vec_entry_vlc[i]); yading@10: } yading@10: } yading@10: yading@10: /* This function returns values in the range yading@10: * (-range + 1; -range/2] U [range/2; range - 1) yading@10: * i.e. yading@10: * nbits = 0 -> 0 yading@10: * nbits = 1 -> -1, 1 yading@10: * nbits = 2 -> -3, -2, 2, 3 yading@10: */ yading@10: static av_always_inline int get_coeff_bits(GetBitContext *gb, int nbits) yading@10: { yading@10: int val; yading@10: yading@10: if (!nbits) yading@10: return 0; yading@10: yading@10: val = get_bits(gb, nbits); yading@10: if (val < (1 << (nbits - 1))) yading@10: val -= (1 << nbits) - 1; yading@10: yading@10: return val; yading@10: } yading@10: yading@10: static inline int get_coeff(GetBitContext *gb, VLC *vlc) yading@10: { yading@10: int val = get_vlc2(gb, vlc->table, vlc->bits, 2); yading@10: yading@10: return get_coeff_bits(gb, val); yading@10: } yading@10: yading@10: static int mss4_decode_dct(GetBitContext *gb, VLC *dc_vlc, VLC *ac_vlc, yading@10: int *block, int *dc_cache, yading@10: int bx, int by, uint16_t *quant_mat) yading@10: { yading@10: int skip, val, pos = 1, zz_pos, dc; yading@10: yading@10: memset(block, 0, sizeof(*block) * 64); yading@10: yading@10: dc = get_coeff(gb, dc_vlc); yading@10: // DC prediction is the same as in MSS3 yading@10: if (by) { yading@10: if (bx) { yading@10: int l, tl, t; yading@10: yading@10: l = dc_cache[LEFT]; yading@10: tl = dc_cache[TOP_LEFT]; yading@10: t = dc_cache[TOP]; yading@10: yading@10: if (FFABS(t - tl) <= FFABS(l - tl)) yading@10: dc += l; yading@10: else yading@10: dc += t; yading@10: } else { yading@10: dc += dc_cache[TOP]; yading@10: } yading@10: } else if (bx) { yading@10: dc += dc_cache[LEFT]; yading@10: } yading@10: dc_cache[LEFT] = dc; yading@10: block[0] = dc * quant_mat[0]; yading@10: yading@10: while (pos < 64) { yading@10: val = get_vlc2(gb, ac_vlc->table, 9, 2); yading@10: if (!val) yading@10: return 0; yading@10: if (val == -1) yading@10: return -1; yading@10: if (val == 0xF0) { yading@10: pos += 16; yading@10: continue; yading@10: } yading@10: skip = val >> 4; yading@10: val = get_coeff_bits(gb, val & 0xF); yading@10: pos += skip; yading@10: if (pos >= 64) yading@10: return -1; yading@10: yading@10: zz_pos = ff_zigzag_direct[pos]; yading@10: block[zz_pos] = val * quant_mat[zz_pos]; yading@10: pos++; yading@10: } yading@10: yading@10: return pos == 64 ? 0 : -1; yading@10: } yading@10: yading@10: static int mss4_decode_dct_block(MSS4Context *c, GetBitContext *gb, yading@10: uint8_t *dst[3], int mb_x, int mb_y) yading@10: { yading@10: int i, j, k, ret; yading@10: uint8_t *out = dst[0]; yading@10: yading@10: for (j = 0; j < 2; j++) { yading@10: for (i = 0; i < 2; i++) { yading@10: int xpos = mb_x * 2 + i; yading@10: c->dc_cache[j][TOP_LEFT] = c->dc_cache[j][TOP]; yading@10: c->dc_cache[j][TOP] = c->prev_dc[0][mb_x * 2 + i]; yading@10: ret = mss4_decode_dct(gb, c->dc_vlc, c->ac_vlc, c->block, yading@10: c->dc_cache[j], yading@10: xpos, mb_y * 2 + j, c->quant_mat[0]); yading@10: if (ret) yading@10: return ret; yading@10: c->prev_dc[0][mb_x * 2 + i] = c->dc_cache[j][LEFT]; yading@10: yading@10: ff_mss34_dct_put(out + xpos * 8, c->pic->linesize[0], yading@10: c->block); yading@10: } yading@10: out += 8 * c->pic->linesize[0]; yading@10: } yading@10: yading@10: for (i = 1; i < 3; i++) { yading@10: c->dc_cache[i + 1][TOP_LEFT] = c->dc_cache[i + 1][TOP]; yading@10: c->dc_cache[i + 1][TOP] = c->prev_dc[i][mb_x]; yading@10: ret = mss4_decode_dct(gb, c->dc_vlc + 1, c->ac_vlc + 1, yading@10: c->block, c->dc_cache[i + 1], mb_x, mb_y, yading@10: c->quant_mat[1]); yading@10: if (ret) yading@10: return ret; yading@10: c->prev_dc[i][mb_x] = c->dc_cache[i + 1][LEFT]; yading@10: yading@10: ff_mss34_dct_put(c->imgbuf[i], 8, c->block); yading@10: out = dst[i] + mb_x * 16; yading@10: // Since the DCT block is coded as YUV420 and the whole frame as YUV444, yading@10: // we need to scale chroma. yading@10: for (j = 0; j < 16; j++) { yading@10: for (k = 0; k < 8; k++) yading@10: AV_WN16A(out + k * 2, c->imgbuf[i][k + (j & ~1) * 4] * 0x101); yading@10: out += c->pic->linesize[i]; yading@10: } yading@10: } yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: static void read_vec_pos(GetBitContext *gb, int *vec_pos, int *sel_flag, yading@10: int *sel_len, int *prev) yading@10: { yading@10: int i, y_flag = 0; yading@10: yading@10: for (i = 2; i >= 0; i--) { yading@10: if (!sel_flag[i]) { yading@10: vec_pos[i] = 0; yading@10: continue; yading@10: } yading@10: if ((!i && !y_flag) || get_bits1(gb)) { yading@10: if (sel_len[i] > 0) { yading@10: int pval = prev[i]; yading@10: vec_pos[i] = get_bits(gb, sel_len[i]); yading@10: if (vec_pos[i] >= pval) yading@10: vec_pos[i]++; yading@10: } else { yading@10: vec_pos[i] = !prev[i]; yading@10: } yading@10: y_flag = 1; yading@10: } else { yading@10: vec_pos[i] = prev[i]; yading@10: } yading@10: } yading@10: } yading@10: yading@10: static int get_value_cached(GetBitContext *gb, int vec_pos, uint8_t *vec, yading@10: int vec_size, int component, int shift, int *prev) yading@10: { yading@10: if (vec_pos < vec_size) yading@10: return vec[vec_pos]; yading@10: if (!get_bits1(gb)) yading@10: return prev[component]; yading@10: prev[component] = get_bits(gb, 8 - shift) << shift; yading@10: return prev[component]; yading@10: } yading@10: yading@10: #define MKVAL(vals) (vals[0] | (vals[1] << 3) | (vals[2] << 6)) yading@10: yading@10: /* Image mode - the hardest to comprehend MSS4 coding mode. yading@10: * yading@10: * In this mode all three 16x16 blocks are coded together with a method yading@10: * remotely similar to the methods employed in MSS1-MSS3. yading@10: * The idea is that every component has a vector of 1-4 most common symbols yading@10: * and an escape mode for reading new value from the bitstream. Decoding yading@10: * consists of retrieving pixel values from the vector or reading new ones yading@10: * from the bitstream; depending on flags read from the bitstream, these vector yading@10: * positions can be updated or reused from the state of the previous line yading@10: * or previous pixel. yading@10: */ yading@10: static int mss4_decode_image_block(MSS4Context *ctx, GetBitContext *gb, yading@10: uint8_t *picdst[3], int mb_x, int mb_y) yading@10: { yading@10: uint8_t vec[3][4]; yading@10: int vec_len[3]; yading@10: int sel_len[3], sel_flag[3]; yading@10: int i, j, k, mode, split; yading@10: int prev_vec1 = 0, prev_split = 0; yading@10: int vals[3] = { 0 }; yading@10: int prev_pix[3] = { 0 }; yading@10: int prev_mode[16] = { 0 }; yading@10: uint8_t *dst[3]; yading@10: yading@10: const int val_shift = ctx->quality == 100 ? 0 : 2; yading@10: yading@10: for (i = 0; i < 3; i++) yading@10: dst[i] = ctx->imgbuf[i]; yading@10: yading@10: for (i = 0; i < 3; i++) { yading@10: vec_len[i] = vec_len_syms[!!i][get_unary(gb, 0, 3)]; yading@10: for (j = 0; j < vec_len[i]; j++) { yading@10: vec[i][j] = get_coeff(gb, &ctx->vec_entry_vlc[!!i]); yading@10: vec[i][j] += ctx->prev_vec[i][j]; yading@10: ctx->prev_vec[i][j] = vec[i][j]; yading@10: } yading@10: sel_flag[i] = vec_len[i] > 1; yading@10: sel_len[i] = vec_len[i] > 2 ? vec_len[i] - 2 : 0; yading@10: } yading@10: yading@10: for (j = 0; j < 16; j++) { yading@10: if (get_bits1(gb)) { yading@10: split = 0; yading@10: if (get_bits1(gb)) { yading@10: prev_mode[0] = 0; yading@10: vals[0] = vals[1] = vals[2] = 0; yading@10: mode = 2; yading@10: } else { yading@10: mode = get_bits1(gb); yading@10: if (mode) yading@10: split = get_bits(gb, 4); yading@10: } yading@10: for (i = 0; i < 16; i++) { yading@10: if (mode <= 1) { yading@10: vals[0] = prev_mode[i] & 7; yading@10: vals[1] = (prev_mode[i] >> 3) & 7; yading@10: vals[2] = prev_mode[i] >> 6; yading@10: if (mode == 1 && i == split) { yading@10: read_vec_pos(gb, vals, sel_flag, sel_len, vals); yading@10: } yading@10: } else if (mode == 2) { yading@10: if (get_bits1(gb)) yading@10: read_vec_pos(gb, vals, sel_flag, sel_len, vals); yading@10: } yading@10: for (k = 0; k < 3; k++) yading@10: *dst[k]++ = get_value_cached(gb, vals[k], vec[k], yading@10: vec_len[k], k, yading@10: val_shift, prev_pix); yading@10: prev_mode[i] = MKVAL(vals); yading@10: } yading@10: } else { yading@10: if (get_bits1(gb)) { yading@10: split = get_bits(gb, 4); yading@10: if (split >= prev_split) yading@10: split++; yading@10: prev_split = split; yading@10: } else { yading@10: split = prev_split; yading@10: } yading@10: if (split) { yading@10: vals[0] = prev_mode[0] & 7; yading@10: vals[1] = (prev_mode[0] >> 3) & 7; yading@10: vals[2] = prev_mode[0] >> 6; yading@10: for (i = 0; i < 3; i++) { yading@10: for (k = 0; k < split; k++) { yading@10: *dst[i]++ = get_value_cached(gb, vals[i], vec[i], yading@10: vec_len[i], i, val_shift, yading@10: prev_pix); yading@10: prev_mode[k] = MKVAL(vals); yading@10: } yading@10: } yading@10: } yading@10: yading@10: if (split != 16) { yading@10: vals[0] = prev_vec1 & 7; yading@10: vals[1] = (prev_vec1 >> 3) & 7; yading@10: vals[2] = prev_vec1 >> 6; yading@10: if (get_bits1(gb)) { yading@10: read_vec_pos(gb, vals, sel_flag, sel_len, vals); yading@10: prev_vec1 = MKVAL(vals); yading@10: } yading@10: for (i = 0; i < 3; i++) { yading@10: for (k = 0; k < 16 - split; k++) { yading@10: *dst[i]++ = get_value_cached(gb, vals[i], vec[i], yading@10: vec_len[i], i, val_shift, yading@10: prev_pix); yading@10: prev_mode[split + k] = MKVAL(vals); yading@10: } yading@10: } yading@10: } yading@10: } yading@10: } yading@10: yading@10: for (i = 0; i < 3; i++) yading@10: for (j = 0; j < 16; j++) yading@10: memcpy(picdst[i] + mb_x * 16 + j * ctx->pic->linesize[i], yading@10: ctx->imgbuf[i] + j * 16, 16); yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: static inline void mss4_update_dc_cache(MSS4Context *c, int mb_x) yading@10: { yading@10: int i; yading@10: yading@10: c->dc_cache[0][TOP] = c->prev_dc[0][mb_x * 2 + 1]; yading@10: c->dc_cache[0][LEFT] = 0; yading@10: c->dc_cache[1][TOP] = 0; yading@10: c->dc_cache[1][LEFT] = 0; yading@10: yading@10: for (i = 0; i < 2; i++) yading@10: c->prev_dc[0][mb_x * 2 + i] = 0; yading@10: yading@10: for (i = 1; i < 3; i++) { yading@10: c->dc_cache[i + 1][TOP] = c->prev_dc[i][mb_x]; yading@10: c->dc_cache[i + 1][LEFT] = 0; yading@10: c->prev_dc[i][mb_x] = 0; yading@10: } yading@10: } yading@10: yading@10: static int mss4_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, yading@10: AVPacket *avpkt) yading@10: { yading@10: const uint8_t *buf = avpkt->data; yading@10: int buf_size = avpkt->size; yading@10: MSS4Context *c = avctx->priv_data; yading@10: GetBitContext gb; yading@10: GetByteContext bc; yading@10: uint8_t *dst[3]; yading@10: int width, height, quality, frame_type; yading@10: int x, y, i, mb_width, mb_height, blk_type; yading@10: int ret; yading@10: yading@10: if (buf_size < HEADER_SIZE) { yading@10: av_log(avctx, AV_LOG_ERROR, yading@10: "Frame should have at least %d bytes, got %d instead\n", yading@10: HEADER_SIZE, buf_size); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: yading@10: bytestream2_init(&bc, buf, buf_size); yading@10: width = bytestream2_get_be16(&bc); yading@10: height = bytestream2_get_be16(&bc); yading@10: bytestream2_skip(&bc, 2); yading@10: quality = bytestream2_get_byte(&bc); yading@10: frame_type = bytestream2_get_byte(&bc); yading@10: yading@10: if (width > avctx->width || yading@10: height != avctx->height) { yading@10: av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d\n", yading@10: width, height); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: if (quality < 1 || quality > 100) { yading@10: av_log(avctx, AV_LOG_ERROR, "Invalid quality setting %d\n", quality); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: if ((frame_type & ~3) || frame_type == 3) { yading@10: av_log(avctx, AV_LOG_ERROR, "Invalid frame type %d\n", frame_type); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: yading@10: if (frame_type != SKIP_FRAME && !bytestream2_get_bytes_left(&bc)) { yading@10: av_log(avctx, AV_LOG_ERROR, yading@10: "Empty frame found but it is not a skip frame.\n"); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: yading@10: if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) yading@10: return ret; yading@10: c->pic->key_frame = (frame_type == INTRA_FRAME); yading@10: c->pic->pict_type = (frame_type == INTRA_FRAME) ? AV_PICTURE_TYPE_I yading@10: : AV_PICTURE_TYPE_P; yading@10: if (frame_type == SKIP_FRAME) { yading@10: *got_frame = 1; yading@10: if ((ret = av_frame_ref(data, c->pic)) < 0) yading@10: return ret; yading@10: yading@10: return buf_size; yading@10: } yading@10: yading@10: if (c->quality != quality) { yading@10: c->quality = quality; yading@10: for (i = 0; i < 2; i++) yading@10: ff_mss34_gen_quant_mat(c->quant_mat[i], quality, !i); yading@10: } yading@10: yading@10: init_get_bits8(&gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE)); yading@10: yading@10: mb_width = FFALIGN(width, 16) >> 4; yading@10: mb_height = FFALIGN(height, 16) >> 4; yading@10: dst[0] = c->pic->data[0]; yading@10: dst[1] = c->pic->data[1]; yading@10: dst[2] = c->pic->data[2]; yading@10: yading@10: memset(c->prev_vec, 0, sizeof(c->prev_vec)); yading@10: for (y = 0; y < mb_height; y++) { yading@10: memset(c->dc_cache, 0, sizeof(c->dc_cache)); yading@10: for (x = 0; x < mb_width; x++) { yading@10: blk_type = decode012(&gb); yading@10: switch (blk_type) { yading@10: case DCT_BLOCK: yading@10: if (mss4_decode_dct_block(c, &gb, dst, x, y) < 0) { yading@10: av_log(avctx, AV_LOG_ERROR, yading@10: "Error decoding DCT block %d,%d\n", yading@10: x, y); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: break; yading@10: case IMAGE_BLOCK: yading@10: if (mss4_decode_image_block(c, &gb, dst, x, y) < 0) { yading@10: av_log(avctx, AV_LOG_ERROR, yading@10: "Error decoding VQ block %d,%d\n", yading@10: x, y); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: break; yading@10: case SKIP_BLOCK: yading@10: if (frame_type == INTRA_FRAME) { yading@10: av_log(avctx, AV_LOG_ERROR, "Skip block in intra frame\n"); yading@10: return AVERROR_INVALIDDATA; yading@10: } yading@10: break; yading@10: } yading@10: if (blk_type != DCT_BLOCK) yading@10: mss4_update_dc_cache(c, x); yading@10: } yading@10: dst[0] += c->pic->linesize[0] * 16; yading@10: dst[1] += c->pic->linesize[1] * 16; yading@10: dst[2] += c->pic->linesize[2] * 16; yading@10: } yading@10: yading@10: if ((ret = av_frame_ref(data, c->pic)) < 0) yading@10: return ret; yading@10: yading@10: *got_frame = 1; yading@10: yading@10: return buf_size; yading@10: } yading@10: yading@10: static av_cold int mss4_decode_init(AVCodecContext *avctx) yading@10: { yading@10: MSS4Context * const c = avctx->priv_data; yading@10: int i; yading@10: yading@10: c->pic = av_frame_alloc(); yading@10: if (!c->pic) yading@10: return AVERROR(ENOMEM); yading@10: yading@10: if (mss4_init_vlcs(c)) { yading@10: av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n"); yading@10: mss4_free_vlcs(c); yading@10: return AVERROR(ENOMEM); yading@10: } yading@10: for (i = 0; i < 3; i++) { yading@10: c->dc_stride[i] = FFALIGN(avctx->width, 16) >> (2 + !!i); yading@10: c->prev_dc[i] = av_malloc(sizeof(**c->prev_dc) * c->dc_stride[i]); yading@10: if (!c->prev_dc[i]) { yading@10: av_log(avctx, AV_LOG_ERROR, "Cannot allocate buffer\n"); yading@10: mss4_free_vlcs(c); yading@10: return AVERROR(ENOMEM); yading@10: } yading@10: } yading@10: yading@10: avctx->pix_fmt = AV_PIX_FMT_YUV444P; yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: static av_cold int mss4_decode_end(AVCodecContext *avctx) yading@10: { yading@10: MSS4Context * const c = avctx->priv_data; yading@10: int i; yading@10: yading@10: av_frame_free(&c->pic); yading@10: yading@10: for (i = 0; i < 3; i++) yading@10: av_freep(&c->prev_dc[i]); yading@10: mss4_free_vlcs(c); yading@10: yading@10: return 0; yading@10: } yading@10: yading@10: AVCodec ff_mts2_decoder = { yading@10: .name = "mts2", yading@10: .type = AVMEDIA_TYPE_VIDEO, yading@10: .id = AV_CODEC_ID_MTS2, yading@10: .priv_data_size = sizeof(MSS4Context), yading@10: .init = mss4_decode_init, yading@10: .close = mss4_decode_end, yading@10: .decode = mss4_decode_frame, yading@10: .capabilities = CODEC_CAP_DR1, yading@10: .long_name = NULL_IF_CONFIG_SMALL("MS Expression Encoder Screen"), yading@10: };