avcodec/rv10: Reduce the size of the tables used to initialize VLCs

This can be achieved by switching to ff_init_vlc_from_lengths() which
allows to replace two uint16_t tables for codes with uint8_t tables for
the symbols by permuting the tables so that the codes are ordered from
left to right in the tree in which case they can be easily computed from
the lengths at runtime.

And after doing so, it became apparent that the tables for the symbols
are actually the same for luma and chroma, so that one can even omit one
of them.

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

1 files changed, 59 insertions, 140 deletions

diff --git a/libavcodec/rv10.c b/libavcodec/rv10.c
index 3a487a6b3e..d1a02d9578 100644
--- a/libavcodec/rv10.c
+++ b/libavcodec/rv10.c
@@ -54,144 +54,63 @@ typedef struct RVDecContext {
     int orig_width, orig_height;
 } RVDecContext;
 
-static const uint16_t rv_lum_code[256] = {
-    0x3e7f, 0x0f00, 0x0f01, 0x0f02, 0x0f03, 0x0f04, 0x0f05, 0x0f06,
-    0x0f07, 0x0f08, 0x0f09, 0x0f0a, 0x0f0b, 0x0f0c, 0x0f0d, 0x0f0e,
-    0x0f0f, 0x0f10, 0x0f11, 0x0f12, 0x0f13, 0x0f14, 0x0f15, 0x0f16,
-    0x0f17, 0x0f18, 0x0f19, 0x0f1a, 0x0f1b, 0x0f1c, 0x0f1d, 0x0f1e,
-    0x0f1f, 0x0f20, 0x0f21, 0x0f22, 0x0f23, 0x0f24, 0x0f25, 0x0f26,
-    0x0f27, 0x0f28, 0x0f29, 0x0f2a, 0x0f2b, 0x0f2c, 0x0f2d, 0x0f2e,
-    0x0f2f, 0x0f30, 0x0f31, 0x0f32, 0x0f33, 0x0f34, 0x0f35, 0x0f36,
-    0x0f37, 0x0f38, 0x0f39, 0x0f3a, 0x0f3b, 0x0f3c, 0x0f3d, 0x0f3e,
-    0x0f3f, 0x0380, 0x0381, 0x0382, 0x0383, 0x0384, 0x0385, 0x0386,
-    0x0387, 0x0388, 0x0389, 0x038a, 0x038b, 0x038c, 0x038d, 0x038e,
-    0x038f, 0x0390, 0x0391, 0x0392, 0x0393, 0x0394, 0x0395, 0x0396,
-    0x0397, 0x0398, 0x0399, 0x039a, 0x039b, 0x039c, 0x039d, 0x039e,
-    0x039f, 0x00c0, 0x00c1, 0x00c2, 0x00c3, 0x00c4, 0x00c5, 0x00c6,
-    0x00c7, 0x00c8, 0x00c9, 0x00ca, 0x00cb, 0x00cc, 0x00cd, 0x00ce,
-    0x00cf, 0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056,
-    0x0057, 0x0020, 0x0021, 0x0022, 0x0023, 0x000c, 0x000d, 0x0004,
-    0x0000, 0x0005, 0x000e, 0x000f, 0x0024, 0x0025, 0x0026, 0x0027,
-    0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x005f,
-    0x00d0, 0x00d1, 0x00d2, 0x00d3, 0x00d4, 0x00d5, 0x00d6, 0x00d7,
-    0x00d8, 0x00d9, 0x00da, 0x00db, 0x00dc, 0x00dd, 0x00de, 0x00df,
-    0x03a0, 0x03a1, 0x03a2, 0x03a3, 0x03a4, 0x03a5, 0x03a6, 0x03a7,
-    0x03a8, 0x03a9, 0x03aa, 0x03ab, 0x03ac, 0x03ad, 0x03ae, 0x03af,
-    0x03b0, 0x03b1, 0x03b2, 0x03b3, 0x03b4, 0x03b5, 0x03b6, 0x03b7,
-    0x03b8, 0x03b9, 0x03ba, 0x03bb, 0x03bc, 0x03bd, 0x03be, 0x03bf,
-    0x0f40, 0x0f41, 0x0f42, 0x0f43, 0x0f44, 0x0f45, 0x0f46, 0x0f47,
-    0x0f48, 0x0f49, 0x0f4a, 0x0f4b, 0x0f4c, 0x0f4d, 0x0f4e, 0x0f4f,
-    0x0f50, 0x0f51, 0x0f52, 0x0f53, 0x0f54, 0x0f55, 0x0f56, 0x0f57,
-    0x0f58, 0x0f59, 0x0f5a, 0x0f5b, 0x0f5c, 0x0f5d, 0x0f5e, 0x0f5f,
-    0x0f60, 0x0f61, 0x0f62, 0x0f63, 0x0f64, 0x0f65, 0x0f66, 0x0f67,
-    0x0f68, 0x0f69, 0x0f6a, 0x0f6b, 0x0f6c, 0x0f6d, 0x0f6e, 0x0f6f,
-    0x0f70, 0x0f71, 0x0f72, 0x0f73, 0x0f74, 0x0f75, 0x0f76, 0x0f77,
-    0x0f78, 0x0f79, 0x0f7a, 0x0f7b, 0x0f7c, 0x0f7d, 0x0f7e, 0x0f7f,
+/* The elements with negative length in the bits table correspond to
+ * open ends in the respective Huffman tree. */
+static const uint8_t rv_sym[] = {
+    128, 127, 129, 125, 126, 130, 131, 121, 122, 123, 124, 132, 133, 134, 135,
+    113, 114, 115, 116, 117, 118, 119, 120, 136, 137, 138, 139, 140, 141, 142,
+    143,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,
+    111, 112, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156,
+    157, 158, 159,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,
+     77,  78,  79,  80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,
+     92,  93,  94,  95,  96, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169,
+    170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184,
+    185, 186, 187, 188, 189, 190, 191,   1,   2,   3,   4,   5,   6,   7,   8,
+      9,  10,  11,  12,  13,  14,  15,  16,  17,  18,  19,  20,  21,  22,  23,
+     24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,  35,  36,  37,  38,
+     39,  40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  51,  52,  53,
+     54,  55,  56,  57,  58,  59,  60,  61,  62,  63,  64, 192, 193, 194, 195,
+    196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210,
+    211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225,
+    226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240,
+    241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255,
+      0,   0,   0,   0,   0,   0,   0,   0,
 };
 
-static const uint8_t rv_lum_bits[256] = {
-    14, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10,  8,  8,  8,  8,  8,  8,  8,
-     8,  8,  8,  8,  8,  8,  8,  8,
-     8,  7,  7,  7,  7,  7,  7,  7,
-     7,  6,  6,  6,  6,  5,  5,  4,
-     2,  4,  5,  5,  6,  6,  6,  6,
-     7,  7,  7,  7,  7,  7,  7,  7,
-     8,  8,  8,  8,  8,  8,  8,  8,
-     8,  8,  8,  8,  8,  8,  8,  8,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
+static const uint8_t rv_lum_len[] = {
+     2,  4,  4,  5,  5,  5,  5,  6,  6,  6,  6,  6,  6,  6,  6,  7,  7,  7,
+     7,  7,  7,  7,  7,  7,  7,  7,  7,  7,  7,  7,  7,  8,  8,  8,  8,  8,
+     8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,
+     8,  8,  8,  8,  8,  8,  8,  8,  8, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+    10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+    10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+    10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+    10, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, -8, -9,-10,-11,-12,-13,-14, 14,
 };
 
-static const uint16_t rv_chrom_code[256] = {
-    0xfe7f, 0x3f00, 0x3f01, 0x3f02, 0x3f03, 0x3f04, 0x3f05, 0x3f06,
-    0x3f07, 0x3f08, 0x3f09, 0x3f0a, 0x3f0b, 0x3f0c, 0x3f0d, 0x3f0e,
-    0x3f0f, 0x3f10, 0x3f11, 0x3f12, 0x3f13, 0x3f14, 0x3f15, 0x3f16,
-    0x3f17, 0x3f18, 0x3f19, 0x3f1a, 0x3f1b, 0x3f1c, 0x3f1d, 0x3f1e,
-    0x3f1f, 0x3f20, 0x3f21, 0x3f22, 0x3f23, 0x3f24, 0x3f25, 0x3f26,
-    0x3f27, 0x3f28, 0x3f29, 0x3f2a, 0x3f2b, 0x3f2c, 0x3f2d, 0x3f2e,
-    0x3f2f, 0x3f30, 0x3f31, 0x3f32, 0x3f33, 0x3f34, 0x3f35, 0x3f36,
-    0x3f37, 0x3f38, 0x3f39, 0x3f3a, 0x3f3b, 0x3f3c, 0x3f3d, 0x3f3e,
-    0x3f3f, 0x0f80, 0x0f81, 0x0f82, 0x0f83, 0x0f84, 0x0f85, 0x0f86,
-    0x0f87, 0x0f88, 0x0f89, 0x0f8a, 0x0f8b, 0x0f8c, 0x0f8d, 0x0f8e,
-    0x0f8f, 0x0f90, 0x0f91, 0x0f92, 0x0f93, 0x0f94, 0x0f95, 0x0f96,
-    0x0f97, 0x0f98, 0x0f99, 0x0f9a, 0x0f9b, 0x0f9c, 0x0f9d, 0x0f9e,
-    0x0f9f, 0x03c0, 0x03c1, 0x03c2, 0x03c3, 0x03c4, 0x03c5, 0x03c6,
-    0x03c7, 0x03c8, 0x03c9, 0x03ca, 0x03cb, 0x03cc, 0x03cd, 0x03ce,
-    0x03cf, 0x00e0, 0x00e1, 0x00e2, 0x00e3, 0x00e4, 0x00e5, 0x00e6,
-    0x00e7, 0x0030, 0x0031, 0x0032, 0x0033, 0x0008, 0x0009, 0x0002,
-    0x0000, 0x0003, 0x000a, 0x000b, 0x0034, 0x0035, 0x0036, 0x0037,
-    0x00e8, 0x00e9, 0x00ea, 0x00eb, 0x00ec, 0x00ed, 0x00ee, 0x00ef,
-    0x03d0, 0x03d1, 0x03d2, 0x03d3, 0x03d4, 0x03d5, 0x03d6, 0x03d7,
-    0x03d8, 0x03d9, 0x03da, 0x03db, 0x03dc, 0x03dd, 0x03de, 0x03df,
-    0x0fa0, 0x0fa1, 0x0fa2, 0x0fa3, 0x0fa4, 0x0fa5, 0x0fa6, 0x0fa7,
-    0x0fa8, 0x0fa9, 0x0faa, 0x0fab, 0x0fac, 0x0fad, 0x0fae, 0x0faf,
-    0x0fb0, 0x0fb1, 0x0fb2, 0x0fb3, 0x0fb4, 0x0fb5, 0x0fb6, 0x0fb7,
-    0x0fb8, 0x0fb9, 0x0fba, 0x0fbb, 0x0fbc, 0x0fbd, 0x0fbe, 0x0fbf,
-    0x3f40, 0x3f41, 0x3f42, 0x3f43, 0x3f44, 0x3f45, 0x3f46, 0x3f47,
-    0x3f48, 0x3f49, 0x3f4a, 0x3f4b, 0x3f4c, 0x3f4d, 0x3f4e, 0x3f4f,
-    0x3f50, 0x3f51, 0x3f52, 0x3f53, 0x3f54, 0x3f55, 0x3f56, 0x3f57,
-    0x3f58, 0x3f59, 0x3f5a, 0x3f5b, 0x3f5c, 0x3f5d, 0x3f5e, 0x3f5f,
-    0x3f60, 0x3f61, 0x3f62, 0x3f63, 0x3f64, 0x3f65, 0x3f66, 0x3f67,
-    0x3f68, 0x3f69, 0x3f6a, 0x3f6b, 0x3f6c, 0x3f6d, 0x3f6e, 0x3f6f,
-    0x3f70, 0x3f71, 0x3f72, 0x3f73, 0x3f74, 0x3f75, 0x3f76, 0x3f77,
-    0x3f78, 0x3f79, 0x3f7a, 0x3f7b, 0x3f7c, 0x3f7d, 0x3f7e, 0x3f7f,
-};
-
-static const uint8_t rv_chrom_bits[256] = {
-    16, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10,  8,  8,  8,  8,  8,  8,  8,
-     8,  6,  6,  6,  6,  4,  4,  3,
-     2,  3,  4,  4,  6,  6,  6,  6,
-     8,  8,  8,  8,  8,  8,  8,  8,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    10, 10, 10, 10, 10, 10, 10, 10,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    12, 12, 12, 12, 12, 12, 12, 12,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
-    14, 14, 14, 14, 14, 14, 14, 14,
+static const uint8_t rv_chrom_len[] = {
+     2,  3,  3,  4,  4,  4,  4,  6,  6,  6,  6,  6,  6,  6,  6,  8,  8,  8,
+     8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8, 10, 10, 10, 10, 10,
+    10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+    10, 10, 10, 10, 10, 10, 10, 10, 10, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
+    12, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
+    14, 14, 14,-10,-11,-12,-13,-14,-15,-16, 16,
 };
 
 static VLC rv_dc_lum, rv_dc_chrom;
@@ -466,12 +385,12 @@ static int rv20_decode_picture_header(RVDecContext *rv)
 
 static av_cold void rv10_init_static(void)
 {
-        INIT_VLC_STATIC(&rv_dc_lum, DC_VLC_BITS, 256,
-                        rv_lum_bits, 1, 1,
-                        rv_lum_code, 2, 2, 16384);
-        INIT_VLC_STATIC(&rv_dc_chrom, DC_VLC_BITS, 256,
-                        rv_chrom_bits, 1, 1,
-                        rv_chrom_code, 2, 2, 16388);
+    INIT_VLC_STATIC_FROM_LENGTHS(&rv_dc_lum, DC_VLC_BITS, 263,
+                                 rv_lum_len, 1,
+                                 rv_sym, 1, 1, 0, 0, 16384);
+    INIT_VLC_STATIC_FROM_LENGTHS(&rv_dc_chrom, DC_VLC_BITS, 263,
+                                 rv_chrom_len, 1,
+                                 rv_sym, 1, 1, 0, 0, 16388);
     ff_h263_decode_init_vlc();
 }