---
Again, some notes:
* This codec is known under many names - M$ Expression Encoder Screen (kinda
commercial name), M$ Titanium Screen 2 (from their Project Titanium, also
explains why its FOURCC is 'MTS2' and not 'MEES') and technically it seems to
be a continuation of MSS series development, so it can be also called MSS4
(which I did for filename).
* I plan to move DCT-related stuff into separate file later because
quantisation tables and DCT are the same.
* Only AC VLC have invalid symbol (long run on ones).
* I don't really understand how VQ (image) block decoding works, so
documentation is welcome ;).
---
Changelog | 1 +
doc/general.texi | 2 +
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/mss4.c | 750 ++++++++++++++++++++++++++++++++++++++++++++++++
libavformat/riff.c | 1 +
7 files changed, 757 insertions(+), 0 deletions(-)
create mode 100644 libavcodec/mss4.c
diff --git a/Changelog b/Changelog
index 39ad8a3..44db4a1 100644
--- a/Changelog
+++ b/Changelog
@@ -31,6 +31,7 @@ version <next>:
- join audio filter
- audio channel mapping filter
- Microsoft ATC Screen decoder
+- Microsoft Expression Encoder Screen decoder
version 0.8:
diff --git a/doc/general.texi b/doc/general.texi
index 4ea47b4..ad764af 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -533,6 +533,8 @@ following image formats are supported:
@item lossless MJPEG @tab X @tab X
@item Microsoft ATC Screen @tab @tab X
@tab Also known as Microsoft Screen 3.
+@item Microsoft EE Screen @tab @tab X
+ @tab Also known as Microsoft Titanium Screen 2.
@item Microsoft RLE @tab @tab X
@item Microsoft Screen 1 @tab @tab X
@tab Also known as Windows Media Video V7 Screen.
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b23bc29..dcd15f6 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -296,6 +296,7 @@ OBJS-$(CONFIG_MSA1_DECODER) += mss3.o
OBJS-$(CONFIG_MSS1_DECODER) += mss1.o
OBJS-$(CONFIG_MSVIDEO1_DECODER) += msvideo1.o
OBJS-$(CONFIG_MSZH_DECODER) += lcldec.o
+OBJS-$(CONFIG_MTS2_DECODER) += mss4.o
OBJS-$(CONFIG_MXPEG_DECODER) += mxpegdec.o mjpegdec.o mjpeg.o
OBJS-$(CONFIG_NELLYMOSER_DECODER) += nellymoserdec.o nellymoser.o
OBJS-$(CONFIG_NELLYMOSER_ENCODER) += nellymoserenc.o nellymoser.o \
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index cb08e33..7b28c34 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -160,6 +160,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (MSS1, mss1);
REGISTER_DECODER (MSVIDEO1, msvideo1);
REGISTER_DECODER (MSZH, mszh);
+ REGISTER_DECODER (MTS2, mts2);
REGISTER_DECODER (MXPEG, mxpeg);
REGISTER_DECODER (NUV, nuv);
REGISTER_ENCDEC (PAM, pam);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 2b70b96..cc1c797 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -257,6 +257,7 @@ enum CodecID {
CODEC_ID_ZEROCODEC,
CODEC_ID_MSS1,
CODEC_ID_MSA1,
+ CODEC_ID_MTS2,
/* various PCM "codecs" */
CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start
of audio codecs
diff --git a/libavcodec/mss4.c b/libavcodec/mss4.c
new file mode 100644
index 0000000..d853695
--- /dev/null
+++ b/libavcodec/mss4.c
@@ -0,0 +1,750 @@
+/*
+ * Microsoft Screen 4 (aka Microsoft Expression Encoder Screen) decoder
+ * Copyright (c) 2012 Konstantin Shishkov
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Microsoft Screen 4 (aka Microsoft Titanium Screen 2,
+ * aka Microsoft Expression Encoder Screen) decoder
+ */
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "get_bits.h"
+#include "unary.h"
+
+#define HEADER_SIZE 8
+
+enum FrameType {
+ INTRA_FRAME = 0,
+ INTER_FRAME,
+ SKIP_FRAME
+};
+
+enum BlockType {
+ SKIP_BLOCK = 0,
+ DCT_BLOCK,
+ IMAGE_BLOCK,
+};
+
+static const uint8_t mss4_dc_vlc_lens[2][16] = {
+ { 0, 1, 5, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0 },
+ { 0, 3, 1, 1, 1, 1, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0 }
+};
+
+static const uint8_t mss4_ac_vlc_lens[2][16] = {
+ { 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 125 },
+ { 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 119 }
+};
+
+static const uint8_t mss4_ac_vlc_syms[2][162] = {
+ {
+ 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
+ 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
+ 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xA1, 0x08,
+ 0x23, 0x42, 0xB1, 0xC1, 0x15, 0x52, 0xD1, 0xF0,
+ 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0A, 0x16,
+ 0x17, 0x18, 0x19, 0x1A, 0x25, 0x26, 0x27, 0x28,
+ 0x29, 0x2A, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
+ 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
+ 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
+ 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
+ 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
+ 0x7A, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
+ 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
+ 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7,
+ 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6,
+ 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5,
+ 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3, 0xD4,
+ 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xE1, 0xE2,
+ 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA,
+ 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8,
+ 0xF9, 0xFA
+ },
+ {
+ 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
+ 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
+ 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
+ 0xA1, 0xB1, 0xC1, 0x09, 0x23, 0x33, 0x52, 0xF0,
+ 0x15, 0x62, 0x72, 0xD1, 0x0A, 0x16, 0x24, 0x34,
+ 0xE1, 0x25, 0xF1, 0x17, 0x18, 0x19, 0x1A, 0x26,
+ 0x27, 0x28, 0x29, 0x2A, 0x35, 0x36, 0x37, 0x38,
+ 0x39, 0x3A, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
+ 0x49, 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
+ 0x59, 0x5A, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+ 0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
+ 0x79, 0x7A, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
+ 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96,
+ 0x97, 0x98, 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5,
+ 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4,
+ 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3,
+ 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2,
+ 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA,
+ 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9,
+ 0xEA, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8,
+ 0xF9, 0xFA
+ }
+};
+
+static const uint8_t vec_len_syms[2][4] = {
+ { 4, 2, 3, 1 },
+ { 4, 1, 2, 3 }
+};
+
+static const uint8_t mss4_vec_entry_vlc_lens[2][16] = {
+ { 0, 2, 2, 3, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
+ { 0, 1, 5, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
+};
+
+static const uint8_t mss4_vec_entry_vlc_syms[2][9] = {
+ { 0, 7, 6, 5, 8, 4, 3, 1, 2 },
+ { 0, 2, 3, 4, 5, 6, 7, 1, 8 }
+};
+
+#define MAX_ENTRIES 162
+
+static const uint8_t mss4_luma_quant[64] = {
+ 16, 11, 10, 16, 24, 40, 51, 61,
+ 12, 12, 14, 19, 26, 58, 60, 55,
+ 14, 13, 16, 24, 40, 57, 69, 56,
+ 14, 17, 22, 29, 51, 87, 80, 62,
+ 18, 22, 37, 56, 68, 109, 103, 77,
+ 24, 35, 55, 64, 81, 104, 113, 92,
+ 49, 64, 78, 87, 103, 121, 120, 101,
+ 72, 92, 95, 98, 112, 100, 103, 99
+};
+
+static const uint8_t mss4_chroma_quant[64] = {
+ 17, 18, 24, 47, 99, 99, 99, 99,
+ 18, 21, 26, 66, 99, 99, 99, 99,
+ 24, 26, 56, 99, 99, 99, 99, 99,
+ 47, 66, 99, 99, 99, 99, 99, 99,
+ 99, 99, 99, 99, 99, 99, 99, 99,
+ 99, 99, 99, 99, 99, 99, 99, 99,
+ 99, 99, 99, 99, 99, 99, 99, 99,
+ 99, 99, 99, 99, 99, 99, 99, 99
+};
+
+static const uint8_t zigzag_scan[64] = {
+ 0, 1, 8, 16, 9, 2, 3, 10,
+ 17, 24, 32, 25, 18, 11, 4, 5,
+ 12, 19, 26, 33, 40, 48, 41, 34,
+ 27, 20, 13, 6, 7, 14, 21, 28,
+ 35, 42, 49, 56, 57, 50, 43, 36,
+ 29, 22, 15, 23, 30, 37, 44, 51,
+ 58, 59, 52, 45, 38, 31, 39, 46,
+ 53, 60, 61, 54, 47, 55, 62, 63
+};
+
+typedef struct MSS4Context {
+ AVFrame pic;
+
+ VLC dc_vlc[2], ac_vlc[2];
+ VLC vec_entry_vlc[2];
+ int block[64];
+ uint8_t imgbuf[3][16 * 16];
+
+ int quality;
+ uint16_t quant_mat[2][64];
+
+ int *prev_dc[3];
+ int prev_dc_stride[3];
+ int prev_dc_height[3];
+
+ int prev_vec[3][4];
+
+ int got_error;
+} MSS4Context;
+
+static int mss4_init_vlc(VLC *vlc, const uint8_t *lens, const uint8_t *syms,
+ int num_syms)
+{
+ uint8_t bits[MAX_ENTRIES];
+ uint16_t codes[MAX_ENTRIES];
+ int i, j;
+ int prefix = 0, max_bits = 0, idx = 0;
+
+ for (i = 0; i < 16; i++) {
+ for (j = 0; j < lens[i]; j++) {
+ bits[idx] = i + 1;
+ codes[idx] = prefix++;
+ max_bits = i + 1;
+ idx++;
+ }
+ prefix <<= 1;
+ }
+
+ return ff_init_vlc_sparse(vlc, FFMIN(max_bits, 9), num_syms, bits, 1, 1,
+ codes, 2, 2, syms, 1, 1, 0);
+}
+
+static int init_vlcs(MSS4Context *ctx)
+{
+ int ret, i;
+
+ for (i = 0; i < 2; i++) {
+ ret = mss4_init_vlc(&ctx->dc_vlc[i], mss4_dc_vlc_lens[i], NULL, 12);
+ if (ret)
+ return ret;
+ ret = mss4_init_vlc(&ctx->ac_vlc[i], mss4_ac_vlc_lens[i],
+ mss4_ac_vlc_syms[i], 162);
+ if (ret)
+ return ret;
+ ret = mss4_init_vlc(&ctx->vec_entry_vlc[i], mss4_vec_entry_vlc_lens[i],
+ mss4_vec_entry_vlc_syms[i], 9);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static void free_vlcs(MSS4Context *ctx)
+{
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ ff_free_vlc(&ctx->dc_vlc[i]);
+ ff_free_vlc(&ctx->ac_vlc[i]);
+ ff_free_vlc(&ctx->vec_entry_vlc[i]);
+ }
+}
+
+static av_always_inline int get_coeff_bits(GetBitContext *gb, int nbits)
+{
+ int val;
+
+ if (!nbits)
+ return 0;
+
+ val = get_bits(gb, nbits);
+ if (val < (1 << (nbits - 1)))
+ val -= (1 << nbits) - 1;
+
+ return val;
+}
+
+static inline int get_coeff(GetBitContext *gb, VLC *vlc)
+{
+ int val;
+
+ val = get_vlc2(gb, vlc->table, vlc->bits, 2);
+
+ return get_coeff_bits(gb, val);
+}
+
+static int decode_dct(GetBitContext *gb, VLC *dc_vlc, VLC *ac_vlc, int *block,
+ int *prev_dc, int prev_dc_stride, int bx, int by,
+ uint16_t *quant_mat)
+{
+ int skip, val, pos = 1, zz_pos, dc;
+
+ memset(block, 0, sizeof(*block) * 64);
+
+ dc = get_coeff(gb, dc_vlc);
+ if (by) {
+ if (bx) {
+ int l, tl, t;
+
+ l = prev_dc[-1];
+ tl = prev_dc[-1 - prev_dc_stride];
+ t = prev_dc[ - prev_dc_stride];
+
+ if (FFABS(t - tl) <= FFABS(l - tl))
+ dc += l;
+ else
+ dc += t;
+ } else {
+ dc += prev_dc[-prev_dc_stride];
+ }
+ } else if (bx) {
+ dc += prev_dc[-1];
+ }
+ prev_dc[0] = dc;
+ block[0] = dc * quant_mat[0];
+
+ while (pos < 64) {
+ val = get_vlc2(gb, ac_vlc->table, 9, 2);
+ if (!val)
+ return 0;
+ if (val == -1)
+ return -1;
+ if (val == 0xF0) {
+ pos += 16;
+ continue;
+ }
+ skip = val >> 4;
+ val = get_coeff_bits(gb, val & 0xF);
+ pos += skip;
+ if (pos >= 64)
+ return -1;
+
+ zz_pos = zigzag_scan[pos];
+ block[zz_pos] = val * quant_mat[zz_pos];
+ pos++;
+ }
+
+ return pos == 64 ? 0 : -1;
+}
+
+#define DCT_TEMPLATE(blk, step, SOP, shift) \
+ const int t0 = -39409 * blk[7 * step] - 58980 * blk[1 * step]; \
+ const int t1 = 39410 * blk[1 * step] - 58980 * blk[7 * step]; \
+ const int t2 = -33410 * blk[5 * step] - 167963 * blk[3 * step]; \
+ const int t3 = 33410 * blk[3 * step] - 167963 * blk[5 * step]; \
+ const int t4 = blk[3 * step] + blk[7 * step]; \
+ const int t5 = blk[1 * step] + blk[5 * step]; \
+ const int t6 = 77062 * t4 + 51491 * t5; \
+ const int t7 = 77062 * t5 - 51491 * t4; \
+ const int t8 = 35470 * blk[2 * step] - 85623 * blk[6 * step]; \
+ const int t9 = 35470 * blk[6 * step] + 85623 * blk[2 * step]; \
+ const int tA = SOP(blk[0 * step] - blk[4 * step]); \
+ const int tB = SOP(blk[0 * step] + blk[4 * step]); \
+ \
+ blk[0 * step] = ( t1 + t6 + t9 + tB) >> shift; \
+ blk[1 * step] = ( t3 + t7 + t8 + tA) >> shift; \
+ blk[2 * step] = ( t2 + t6 - t8 + tA) >> shift; \
+ blk[3 * step] = ( t0 + t7 - t9 + tB) >> shift; \
+ blk[4 * step] = (-(t0 + t7) - t9 + tB) >> shift; \
+ blk[5 * step] = (-(t2 + t6) - t8 + tA) >> shift; \
+ blk[6 * step] = (-(t3 + t7) + t8 + tA) >> shift; \
+ blk[7 * step] = (-(t1 + t6) + t9 + tB) >> shift; \
+
+#define SOP_ROW(a) ((a) << 16) + 0x2000
+#define SOP_COL(a) ((a + 32) << 16)
+
+static void dct_put(uint8_t *dst, int stride, int *block)
+{
+ int i, j;
+ int *ptr;
+
+ ptr = block;
+ for (i = 0; i < 8; i++) {
+ DCT_TEMPLATE(ptr, 1, SOP_ROW, 13);
+ ptr += 8;
+ }
+
+ ptr = block;
+ for (i = 0; i < 8; i++) {
+ DCT_TEMPLATE(ptr, 8, SOP_COL, 22);
+ ptr++;
+ }
+
+ ptr = block;
+ for (j = 0; j < 8; j++) {
+ for (i = 0; i < 8; i++)
+ dst[i] = av_clip_uint8(ptr[i] + 128);
+ dst += stride;
+ ptr += 8;
+ }
+}
+
+static void gen_quant_mat(uint16_t *qmat, const uint8_t *ref, float scale)
+{
+ int i;
+
+ for (i = 0; i < 64; i++)
+ qmat[i] = (uint16_t)(ref[i] * scale + 50.0) / 100;
+}
+
+static void decode_dct_block(MSS4Context *c, GetBitContext *gb,
+ uint8_t *dst[3], int mb_x, int mb_y)
+{
+ int i, j, k, ret;
+ int *prev_dc;
+ uint8_t *out = dst[0];
+
+ prev_dc = c->prev_dc[0] + c->prev_dc_stride[0] + mb_x * 2;
+ for (j = 0; j < 2; j++) {
+ for (i = 0; i < 2; i++) {
+ int xpos = mb_x * 2 + i;
+ ret = decode_dct(gb, c->dc_vlc, c->ac_vlc, c->block, prev_dc + i,
+ c->prev_dc_stride[0], xpos, mb_y * 2 + j,
+ c->quant_mat[0]);
+ if (ret) {
+ c->got_error = 1;
+ return;
+ }
+ dct_put(out + xpos * 8, c->pic.linesize[0],
+ c->block);
+ }
+ out += 8 * c->pic.linesize[0];
+ prev_dc += c->prev_dc_stride[0];
+ }
+
+ for (i = 1; i < 3; i++) {
+ ret = decode_dct(gb, c->dc_vlc + 1, c->ac_vlc + 1,
+ c->block,
+ c->prev_dc[i] + mb_x + c->prev_dc_stride[i],
+ c->prev_dc_stride[i], mb_x, mb_y,
+ c->quant_mat[1]);
+ if (ret) {
+ c->got_error = 1;
+ return;
+ }
+ dct_put(c->imgbuf[i], 8, c->block);
+ out = dst[i] + mb_x * 16;
+ for (j = 0; j < 16; j++) {
+ for (k = 0; k < 8; k++)
+ AV_WN16A(out + k * 2, c->imgbuf[i][k + (j & ~1) * 4] * 0x101);
+ out += c->pic.linesize[i];
+ }
+ }
+}
+
+static void read_vec_pos(GetBitContext *gb, int *vec_pos, int *sel_flag,
+ int *sel_len, int *prev)
+{
+ int i, y_flag = 0;
+
+ for (i = 2; i >= 0; i--) {
+ if (!sel_flag[i]) {
+ vec_pos[i] = 0;
+ continue;
+ }
+ if ((!i && !y_flag) || get_bits1(gb)) {
+ if (sel_len[i] > 0) {
+ int pval = prev[i];
+ vec_pos[i] = get_bits(gb, sel_len[i]);
+ if (vec_pos[i] >= pval)
+ vec_pos[i]++;
+ } else {
+ vec_pos[i] = !prev[i];
+ }
+ y_flag = 1;
+ } else {
+ vec_pos[i] = prev[i];
+ }
+ }
+}
+
+static int get_value_cached(GetBitContext *gb, int vec_pos, uint8_t *vec,
+ int vec_size, int component, int shift, int *prev)
+{
+ if (vec_pos < vec_size)
+ return vec[vec_pos];
+ if (!get_bits1(gb))
+ return prev[component];
+ prev[component] = get_bits(gb, 8 - shift) << shift;
+ return prev[component];
+}
+
+#define MKVAL(vals) (vals[0] | (vals[1] << 3) | (vals[2] << 6))
+
+static void decode_image_block(MSS4Context *ctx, GetBitContext *gb,
+ uint8_t *picdst[3], int mb_x, int mb_y)
+{
+ uint8_t vec[3][4];
+ int vec_len[3];
+ int sel_len[3], sel_flag[3];
+ int i, j, k, mode, split;
+ int prev_vec1 = 0, prev_split = 0;
+ int vals[3], prev_pix[3];
+ int prev_mode[16];
+ uint8_t *dst[3];
+
+ const int val_shift = ctx->quality == 100 ? 0 : 2;
+
+ for (i = 0; i < 3; i++)
+ dst[i] = ctx->imgbuf[i];
+ memset(prev_mode, 0, sizeof(prev_mode));
+ memset(prev_pix, 0, sizeof(prev_pix));
+ memset(vals, 0, sizeof(vals));
+ prev_vec1 = 0;
+
+ for (i = 0; i < 3; i++) {
+ vec_len[i] = vec_len_syms[!!i][get_unary(gb, 0, 3)];
+ for (j = 0; j < vec_len[i]; j++) {
+ vec[i][j] = get_coeff(gb, &ctx->vec_entry_vlc[!!i]);
+ vec[i][j] += ctx->prev_vec[i][j];
+ ctx->prev_vec[i][j] = vec[i][j];
+ }
+ sel_flag[i] = vec_len[i] > 1;
+ sel_len[i] = vec_len[i] > 2 ? vec_len[i] - 2 : 0;
+ }
+
+ for (j = 0; j < 16; j++) {
+ if (get_bits1(gb)) {
+ split = 0;
+ if (get_bits1(gb)) {
+ prev_mode[0] = 0;
+ vals[0] = vals[1] = vals[2] = 0;
+ mode = 2;
+ } else {
+ mode = get_bits1(gb);
+ if (mode)
+ split = get_bits(gb, 4);
+ }
+ for (i = 0; i < 16; i++) {
+ if (mode <= 1) {
+ vals[0] = prev_mode[i] & 7;
+ vals[1] = (prev_mode[i] >> 3) & 7;
+ vals[2] = prev_mode[i] >> 6;
+ if (mode == 1 && i == split) {
+ read_vec_pos(gb, vals, sel_flag, sel_len, vals);
+ }
+ } else if (mode == 2) {
+ if (get_bits1(gb))
+ read_vec_pos(gb, vals, sel_flag, sel_len, vals);
+ }
+ for (k = 0; k < 3; k++)
+ *dst[k]++ = get_value_cached(gb, vals[k], vec[k],
+ vec_len[k], k,
+ val_shift, prev_pix);
+ prev_mode[i] = MKVAL(vals);
+ }
+ } else {
+ if (get_bits1(gb)) {
+ split = get_bits(gb, 4);
+ if (split >= prev_split)
+ split++;
+ prev_split = split;
+ } else {
+ split = prev_split;
+ }
+ if (split) {
+ vals[0] = prev_mode[0] & 7;
+ vals[1] = (prev_mode[0] >> 3) & 7;
+ vals[2] = prev_mode[0] >> 6;
+ for (i = 0; i < 3; i++) {
+ for (k = 0; k < split; k++) {
+ *dst[i]++ = get_value_cached(gb, vals[i], vec[i],
+ vec_len[i], i, val_shift,
+ prev_pix);
+ prev_mode[k] = MKVAL(vals);
+ }
+ }
+ }
+
+ if (split != 16) {
+ vals[0] = prev_vec1 & 7;
+ vals[1] = (prev_vec1 >> 3) & 7;
+ vals[2] = prev_vec1 >> 6;
+ if (get_bits1(gb)) {
+ read_vec_pos(gb, vals, sel_flag, sel_len, vals);
+ prev_vec1 = MKVAL(vals);
+ }
+ for (i = 0; i < 3; i++) {
+ for (k = 0; k < 16 - split; k++) {
+ *dst[i]++ = get_value_cached(gb, vals[i], vec[i],
+ vec_len[i], i, val_shift,
+ prev_pix);
+ prev_mode[split + k] = MKVAL(vals);
+ }
+ }
+ }
+ }
+ }
+
+ for (i = 0; i < 3; i++)
+ for (j = 0; j < 16; j++)
+ memcpy(picdst[i] + mb_x * 16 + j * ctx->pic.linesize[i],
+ ctx->imgbuf[i] + j * 16, 16);
+}
+
+static int mss4_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
+ AVPacket *avpkt)
+{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ MSS4Context *c = avctx->priv_data;
+ GetBitContext gb;
+ GetByteContext bc;
+ uint8_t *dst[3];
+ int width, height, quality, frame_type;
+ int x, y, i, mb_width, mb_height, blk_type;
+ int ret;
+
+ if (buf_size < HEADER_SIZE) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Frame should have at least %d bytes, got %d instead\n",
+ HEADER_SIZE, buf_size);
+ return AVERROR_INVALIDDATA;
+ }
+
+ bytestream2_init(&bc, buf, buf_size);
+ width = bytestream2_get_be16(&bc);
+ height = bytestream2_get_be16(&bc);
+ bytestream2_skip(&bc, 2);
+ quality = bytestream2_get_byte(&bc);
+ frame_type = bytestream2_get_byte(&bc);
+
+ if (width > avctx->width ||
+ height != avctx->height) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d\n",
+ width, height);
+ return AVERROR_INVALIDDATA;
+ }
+ if (quality < 1 || quality > 100) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid quality setting %d\n", quality);
+ return AVERROR_INVALIDDATA;
+ }
+ if ((frame_type & ~3) || frame_type == 3) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid frame type %d\n", frame_type);
+ return AVERROR_INVALIDDATA;
+ }
+
+ if (frame_type != SKIP_FRAME && !bytestream2_get_bytes_left(&bc)) {
+ av_log(avctx, AV_LOG_ERROR, "Not skip frame without data found\n");
+ return AVERROR_INVALIDDATA;
+ }
+ if (frame_type != INTRA_FRAME && c->got_error)
+ return buf_size;
+ c->got_error = 0;
+
+ c->pic.reference = 3;
+ c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
+ FF_BUFFER_HINTS_REUSABLE;
+ if ((ret = avctx->reget_buffer(avctx, &c->pic)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
+ return ret;
+ }
+ c->pic.key_frame = (frame_type == INTRA_FRAME);
+ c->pic.pict_type = (frame_type == INTRA_FRAME) ? AV_PICTURE_TYPE_I
+ : AV_PICTURE_TYPE_P;
+ if (frame_type == SKIP_FRAME) {
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = c->pic;
+
+ return buf_size;
+ }
+
+ if (c->quality != quality) {
+ float scale;
+ c->quality = quality;
+ if (quality > 50)
+ scale = 200.0f - 2 * quality;
+ else
+ scale = 5000.0f / quality;
+ for (i = 0; i < 2; i++)
+ gen_quant_mat(c->quant_mat[i],
+ i ? mss4_chroma_quant : mss4_luma_quant,
+ scale);
+ }
+
+ init_get_bits(&gb, buf + HEADER_SIZE, (buf_size - HEADER_SIZE) * 8);
+
+ mb_width = FFALIGN(width, 16) >> 4;
+ mb_height = FFALIGN(height, 16) >> 4;
+ dst[0] = c->pic.data[0];
+ dst[1] = c->pic.data[1];
+ dst[2] = c->pic.data[2];
+
+ for (i = 0; i < 3; i++)
+ memset(c->prev_dc[i], 0, sizeof(**c->prev_dc) * c->prev_dc_stride[i] *
c->prev_dc_height[i]);
+ memset(c->prev_vec, 0, sizeof(c->prev_vec));
+ for (y = 0; y < mb_height; y++) {
+ for (x = 0; x < mb_width; x++) {
+ blk_type = decode012(&gb);
+ switch (blk_type) {
+ case DCT_BLOCK:
+ decode_dct_block(c, &gb, dst, x, y);
+ break;
+ case IMAGE_BLOCK:
+ decode_image_block(c, &gb, dst, x, y);
+ break;
+ case SKIP_BLOCK:
+ if (frame_type == INTRA_FRAME) {
+ av_log(avctx, AV_LOG_ERROR, "Skip block in intra frame\n");
+ c->got_error = 1;
+ }
+ break;
+ }
+ if (c->got_error) {
+ av_log(avctx, AV_LOG_ERROR, "Error decoding block %d,%d\n",
+ x, y);
+ return AVERROR_INVALIDDATA;
+ }
+ }
+ dst[0] += c->pic.linesize[0] * 16;
+ dst[1] += c->pic.linesize[1] * 16;
+ dst[2] += c->pic.linesize[2] * 16;
+ for (i = 0; i < 3; i++) {
+ memmove(c->prev_dc[i],
+ c->prev_dc[i] + c->prev_dc_stride[i]
+ * (c->prev_dc_height[i] - 1),
+ sizeof(**c->prev_dc) * c->prev_dc_stride[i]);
+ memset(c->prev_dc[i] + c->prev_dc_stride[i], 0,
+ sizeof(**c->prev_dc) * c->prev_dc_stride[i] *
+ (c->prev_dc_height[i] - 1));
+ }
+ }
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = c->pic;
+
+ return buf_size;
+}
+
+static av_cold int mss4_decode_init(AVCodecContext *avctx)
+{
+ MSS4Context * const c = avctx->priv_data;
+ int i;
+
+ c->got_error = 0;
+ if (init_vlcs(c)) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");
+ free_vlcs(c);
+ return AVERROR(ENOMEM);
+ }
+ for (i = 0; i < 3; i++) {
+ int b_width = FFALIGN(avctx->width, 16) >> (2 + !!i);
+ int b_height = 2 + !i;
+ c->prev_dc_stride[i] = b_width;
+ c->prev_dc_height[i] = b_height;
+ c->prev_dc[i] = av_malloc(sizeof(**c->prev_dc) *
+ b_width * b_height);
+ if (!c->prev_dc[i]) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot allocate buffer\n");
+ free_vlcs(c);
+ return AVERROR(ENOMEM);
+ }
+ }
+
+ avctx->pix_fmt = PIX_FMT_YUV444P;
+ avctx->coded_frame = &c->pic;
+
+ return 0;
+}
+
+static av_cold int mss4_decode_end(AVCodecContext *avctx)
+{
+ MSS4Context * const c = avctx->priv_data;
+ int i;
+
+ if (c->pic.data[0])
+ avctx->release_buffer(avctx, &c->pic);
+ for (i = 0; i < 3; i++)
+ av_freep(&c->prev_dc[i]);
+ free_vlcs(c);
+
+ return 0;
+}
+
+AVCodec ff_mts2_decoder = {
+ .name = "mts2",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = CODEC_ID_MTS2,
+ .priv_data_size = sizeof(MSS4Context),
+ .init = mss4_decode_init,
+ .close = mss4_decode_end,
+ .decode = mss4_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("MS Expression Encoder Screen"),
+};
diff --git a/libavformat/riff.c b/libavformat/riff.c
index 0aef2d7..867a9e5 100644
--- a/libavformat/riff.c
+++ b/libavformat/riff.c
@@ -286,6 +286,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
{ CODEC_ID_ZEROCODEC, MKTAG('Z', 'E', 'C', 'O') },
{ CODEC_ID_MSS1, MKTAG('M', 'S', 'S', '1') },
{ CODEC_ID_MSA1, MKTAG('M', 'S', 'A', '1') },
+ { CODEC_ID_MTS2, MKTAG('M', 'T', 'S', '2') },
{ CODEC_ID_NONE, 0 }
};
--
1.7.0.4
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