avcodec/imc: Make Huffman tables smaller

The IMC decoder uses Huffman tables which are created at runtime from
length tables of type uint8_t and code tables of type uint16_t together
with an implicit symbols table (i.e. symbol[i] == i). This commit
changes this: All three tables are subjected to the same permutation to
order the codes from left to right in the tree; afterwards the codes can
be omitted because they are easily computable at runtime from the
lengths, whereas the symbols need to be explicitly coded now. But said
symbols fit into an uint8_t, so one saves space.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

diff --git a/libavcodec/imc.c b/libavcodec/imc.c
index 70ad5b1dbdcdc398e8c2bba2be98c54886a6e322..5a1649ab624dbc851343b9225ca31b0158b4a0e7 100644 (file)
--- a/libavcodec/imc.c
+++ b/libavcodec/imc.c
@@ -239,9 +239,10 @@ static av_cold int imc_decode_init(AVCodecContext *avctx)
         for (j = 0; j < 4; j++) {
             huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]];
             huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
-            init_vlc(&huffman_vlc[i][j], IMC_VLC_BITS, imc_huffman_sizes[i],
-                     imc_huffman_lens[i][j], 1, 1,
-                     imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
+            ff_init_vlc_from_lengths(&huffman_vlc[i][j], IMC_VLC_BITS, imc_huffman_sizes[i],
+                                     imc_huffman_lens[i][j], 1,
+                                     imc_huffman_syms[i][j], 1, 1,
+                                     0, INIT_VLC_USE_NEW_STATIC, NULL);
         }
     }
 

diff --git a/libavcodec/imcdata.h b/libavcodec/imcdata.h
index 64e7c7185e151da12132aa6a4a8785d9a4bf4578..46037bd555d381ee92af0e00b3194d910ed9e3d4 100644 (file)
--- a/libavcodec/imcdata.h
+++ b/libavcodec/imcdata.h
@@ -114,55 +114,55 @@ static const uint8_t imc_huffman_sizes[4] = {
 
 static const uint8_t imc_huffman_lens[4][4][18] = {
     {
-        { 16, 15, 13, 11,  8,  5,  3,  1,  2,  4,  6,  9, 10, 12, 14, 16,  7,  0 },
-        { 10,  8,  7,  6,  4,  4,  3,  2,  2,  3,  4,  6,  7,  9, 11, 11,  7,  0 },
-        { 15, 15, 14, 11,  8,  6,  4,  2,  1,  4,  5,  7,  9, 10, 12, 13,  4,  0 },
-        { 13, 11, 10,  8,  6,  4,  2,  2,  2,  3,  5,  7,  9, 12, 15, 15, 14,  0 },
+        { 1,  2,  5,  6, 11, 12, 15, 16, 16, 14, 13, 10,  9,  8,  7,  4,  3 },
+        { 2,  3,  3,  4,  4,  4,  6,  6,  7,  7,  7,  8,  9, 10, 11, 11,  2 },
+        { 1,  4,  4,  7,  9, 10, 12, 15, 15, 14, 13, 11,  8,  6,  5,  4,  2 },
+        { 2,  2,  4,  8,  9, 14, 15, 15, 13, 12, 11, 10,  7,  6,  5,  3,  2 },
     },
     {
-        { 14, 12, 10,  8,  7,  4,  2,  2,  2,  3,  5,  7,  9, 11, 13, 14,  7,  0 },
-        { 14, 13, 11,  8,  6,  4,  3,  2,  2,  3,  5,  7,  9, 10, 12, 14,  3,  0 },
-        { 13, 12, 10,  7,  5,  4,  3,  2,  2,  3,  4,  6,  8,  9, 11, 13,  4,  0 },
-        { 13, 12, 10,  7,  5,  4,  3,  2,  2,  3,  4,  6,  8,  9, 11, 13,  4,  0 },
+        { 2,  2,  3,  4,  7,  7, 10, 11, 12, 14, 14, 13,  9,  8,  7,  5,  2 },
+        { 2,  3, 14, 14, 13, 12, 11, 10,  9,  8,  7,  6,  5,  4,  3,  3,  2 },
+        { 2,  3,  3,  4,  4,  5,  7,  9, 11, 12, 13, 13, 10,  8,  6,  4,  2 },
+        { 2,  3,  3,  4,  4,  5,  7,  9, 11, 12, 13, 13, 10,  8,  6,  4,  2 },
     },
     {
-        { 16, 14, 12, 10,  8,  5,  3,  1,  2,  4,  7,  9, 11, 13, 15, 17,  6, 17 },
-        { 15, 13, 11,  8,  6,  4,  2,  2,  2,  3,  5,  7, 10, 12, 14, 16,  9, 16 },
-        { 14, 12, 11,  9,  8,  6,  3,  1,  2,  5,  7, 10, 13, 15, 16, 17,  4, 17 },
-        { 16, 14, 12,  9,  7,  5,  2,  2,  2,  3,  4,  6,  8, 11, 13, 15, 10, 16 },
+        { 3,  5,  8,  9, 12, 15, 17, 17, 16, 14, 13, 11, 10,  7,  6,  4,  2,  1 },
+        { 4,  7,  8, 10, 11, 12, 15, 16, 16, 14, 13,  9,  6,  5,  3,  2,  2,  2 },
+        { 4,  5,  6,  7, 12, 13, 17, 17, 16, 15, 14, 11, 10,  9,  8,  3,  2,  1 },
+        { 2,  5,  7,  8, 14, 15, 16, 16, 13, 12, 11, 10,  9,  6,  4,  3,  2,  2 },
     },
     {
-        { 13, 11, 10,  8,  7,  5,  2,  2,  2,  4,  6,  9, 12, 14, 15, 16,  3, 16 },
-        { 11, 11, 10,  9,  8,  7,  5,  4,  3,  3,  3,  3,  3,  3,  4,  5,  6,  5 },
-        {  9,  9,  7,  6,  5,  4,  3,  3,  2,  3,  4,  5,  4,  5,  5,  6,  8,  6 },
-        { 13, 12, 10,  8,  5,  3,  3,  2,  2,  3,  4,  7,  9, 11, 14, 15,  6, 15 },
+        { 2,  4,  7,  9, 10, 12, 13, 15, 16, 16, 14, 11,  8,  6,  5,  3,  2,  2 },
+        { 3,  5,  5,  7, 10, 11, 11,  9,  8,  6,  5,  4,  4,  3,  3,  3,  3,  3 },
+        { 5,  8,  9,  9,  7,  6,  6,  6,  5,  5,  5,  4,  4,  4,  3,  3,  3,  2 },
+        { 2,  3,  5,  7,  8, 11, 12, 13, 15, 15, 14, 10,  9,  6,  4,  3,  3,  2 },
     }
 };
 
-static const uint16_t imc_huffman_bits[4][4][18] = {
+static const uint8_t imc_huffman_syms[4][4][18] = {
     {
-        { 0xCC32, 0x6618, 0x1987, 0x0660, 0x00CD, 0x0018, 0x0007, 0x0000, 0x0002, 0x000D, 0x0032, 0x0199, 0x0331, 0x0CC2, 0x330D, 0xCC33, 0x0067, 0x0000 },
-        { 0x02FE, 0x00BE, 0x005E, 0x002D, 0x000A, 0x0009, 0x0003, 0x0003, 0x0000, 0x0002, 0x0008, 0x002C, 0x005D, 0x017E, 0x05FE, 0x05FF, 0x005C, 0x0000 },
-        { 0x5169, 0x5168, 0x28B5, 0x0517, 0x00A3, 0x0029, 0x0008, 0x0003, 0x0000, 0x0009, 0x0015, 0x0050, 0x0144, 0x028A, 0x0A2C, 0x145B, 0x000B, 0x0000 },
-        { 0x1231, 0x048D, 0x0247, 0x0090, 0x0025, 0x0008, 0x0001, 0x0003, 0x0000, 0x0005, 0x0013, 0x0049, 0x0122, 0x0919, 0x48C3, 0x48C2, 0x2460, 0x0000 },
+        {  7,  8,  5, 10,  3, 13,  1,  0, 15, 14,  2, 12, 11,  4, 16,  9,  6 },
+        {  8,  9,  6, 10,  5,  4, 11,  3, 16, 12,  2,  1, 13,  0, 14, 15,  7 },
+        {  8,  6,  9, 11, 12, 13, 14,  1,  0,  2, 15,  3,  4,  5, 10, 16,  7 },
+        {  8,  6,  5,  3, 12, 16, 15, 14,  0, 13,  1,  2, 11,  4, 10,  9,  7 },
     },
     {
-        { 0x2D1D, 0x0B46, 0x02D0, 0x00B5, 0x0059, 0x000A, 0x0003, 0x0001, 0x0000, 0x0004, 0x0017, 0x005B, 0x0169, 0x05A2, 0x168F, 0x2D1C, 0x0058, 0x0000 },
-        { 0x1800, 0x0C01, 0x0301, 0x0061, 0x0019, 0x0007, 0x0004, 0x0003, 0x0000, 0x0005, 0x000D, 0x0031, 0x00C1, 0x0181, 0x0601, 0x1801, 0x0002, 0x0000 },
-        { 0x1556, 0x0AAA, 0x02AB, 0x0054, 0x0014, 0x000B, 0x0002, 0x0003, 0x0000, 0x0003, 0x0008, 0x002B, 0x00AB, 0x0154, 0x0554, 0x1557, 0x0009, 0x0000 },
-        { 0x1556, 0x0AAA, 0x02AB, 0x0054, 0x0014, 0x000B, 0x0002, 0x0003, 0x0000, 0x0003, 0x0008, 0x002B, 0x00AB, 0x0154, 0x0554, 0x1557, 0x0009, 0x0000 },
+        {  8,  7,  9,  5, 16,  4,  2, 13,  1, 15,  0, 14, 12,  3, 11, 10,  6 },
+        {  8, 16,  0, 15,  1, 14,  2, 13, 12,  3, 11,  4, 10,  5,  6,  9,  7 },
+        {  8,  6,  9, 10, 16,  4,  3, 13, 14,  1,  0, 15,  2, 12, 11,  5,  7 },
+        {  8,  6,  9, 10, 16,  4,  3, 13, 14,  1,  0, 15,  2, 12, 11,  5,  7 },
     },
     {
-        { 0x2993, 0x0A65, 0x0298, 0x00A7, 0x0028, 0x0004, 0x0000, 0x0001, 0x0001, 0x0003, 0x0015, 0x0052, 0x014D, 0x0533, 0x14C8, 0x5324, 0x000B, 0x5325 },
-        { 0x09B8, 0x026F, 0x009A, 0x0012, 0x0005, 0x0000, 0x0001, 0x0002, 0x0003, 0x0001, 0x0003, 0x0008, 0x004C, 0x0136, 0x04DD, 0x1373, 0x0027, 0x1372 },
-        { 0x0787, 0x01E0, 0x00F1, 0x003D, 0x001F, 0x0006, 0x0001, 0x0001, 0x0001, 0x0002, 0x000E, 0x0079, 0x03C2, 0x0F0D, 0x1E19, 0x3C30, 0x0000, 0x3C31 },
-        { 0x4B06, 0x12C0, 0x04B1, 0x0097, 0x0024, 0x0008, 0x0002, 0x0003, 0x0000, 0x0003, 0x0005, 0x0013, 0x004A, 0x0259, 0x0961, 0x2582, 0x012D, 0x4B07 },
+        {  6,  5,  4, 11,  2, 14, 15, 17,  0,  1, 13, 12,  3, 10, 16,  9,  8,  7 },
+        {  5, 11,  3, 12,  2, 13,  0, 17, 15, 14,  1, 16,  4, 10,  9,  6,  7,  8 },
+        { 16,  9,  5, 10,  1, 12, 15, 17, 14, 13,  0,  2, 11,  3,  4,  6,  8,  7 },
+        {  8,  5,  4, 12,  1, 15,  0, 17, 14,  2, 13, 16,  3, 11, 10,  9,  6,  7 },
     },
     {
-        { 0x0A5A, 0x0297, 0x014A, 0x0053, 0x0028, 0x000B, 0x0003, 0x0000, 0x0002, 0x0004, 0x0015, 0x00A4, 0x052C, 0x14B7, 0x296C, 0x52DB, 0x0003, 0x52DA },
-        { 0x0193, 0x0192, 0x00C8, 0x0065, 0x0033, 0x0018, 0x0007, 0x0004, 0x0000, 0x0004, 0x0005, 0x0007, 0x0006, 0x0003, 0x0005, 0x0005, 0x000D, 0x0004 },
-        { 0x0012, 0x0013, 0x0005, 0x0003, 0x0000, 0x0003, 0x0005, 0x0004, 0x0003, 0x0003, 0x0005, 0x0005, 0x0004, 0x0004, 0x0003, 0x0005, 0x0008, 0x0004 },
-        { 0x0D66, 0x06B2, 0x01AD, 0x006A, 0x000C, 0x0005, 0x0004, 0x0000, 0x0003, 0x0002, 0x0007, 0x0034, 0x00D7, 0x0358, 0x1ACF, 0x359C, 0x001B, 0x359D },
+        {  7,  9,  4, 11,  2, 12,  0, 14, 17, 15, 13,  1,  3, 10,  5, 16,  8,  6 },
+        {  8, 17, 15,  5,  2,  1,  0,  3,  4, 16,  6,  7, 14, 13,  9, 10, 12, 11 },
+        {  4, 16,  0,  1,  2,  3, 17, 15, 14, 13, 11,  5, 12, 10,  9,  7,  6,  8 },
+        {  7,  9,  4, 11,  3, 13,  1,  0, 15, 17, 14,  2, 12, 16, 10,  6,  5,  8 },
     }
 };