avcodec/atrac3plus: Run-length encode length tables to make them smaller

This is very beneficial for the scale factor tables where 4*64+4*15
bytes of length information can be replaced by eight codebooks of 12
bytes each; furthermore the number of codes as well as the maximum
length of a code can be easily derived from said codebooks, making
tables containing said information superfluous. This and combining the
symbols into one big array also made an array of pointers to the tables
redundant.

For the wordlen and code table tables the benefits are not that big
(given these tables don't contain that many elements), but all in all
using codebooks is also advantageouos for them. Therefore it has been
done.

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

diff --git a/libavcodec/atrac3plus.c b/libavcodec/atrac3plus.c
index 984b06fbe468848b9e71153873ed22e032a9aea6..3a0a0d5f360827d8bc1daf6bc3d4d84cd5557ace 100644 (file)
--- a/libavcodec/atrac3plus.c
+++ b/libavcodec/atrac3plus.c
@@ -78,55 +78,18 @@ av_cold void ff_atrac3p_init_vlcs(void)
     int i, tab_offset = 0;
     const uint8_t *xlats;
 
-    static const uint8_t wl_nb_bits[4]  = { 2, 3, 5, 5 };
-    static const uint8_t wl_nb_codes[4] = { 3, 5, 8, 8 };
-    static const uint8_t (*const wl_huffs[4])[2] = {
-        atrac3p_wl_huff1, atrac3p_wl_huff2,
-        atrac3p_wl_huff3, atrac3p_wl_huff4
-    };
-
-    static const uint8_t ct_nb_bits[4]  = { 3, 4, 4, 4 };
-    static const uint8_t ct_nb_codes[4] = { 4, 8, 8, 8 };
-    static const uint8_t (*const ct_huffs[4])[2]  = {
-        atrac3p_ct_huff1, atrac3p_ct_huff2,
-        atrac3p_ct_huff3, atrac3p_ct_huff4
-    };
-
-    static const uint8_t sf_nb_bits[8]  = {  9,  9,  9,  9,  6,  6,  7,  7 };
-    static const uint8_t sf_nb_codes[8] = { 64, 64, 64, 64, 15, 15, 15, 15 };
-    static const uint8_t  (*const sf_huffs[8])[2]  = {
-        atrac3p_sf_huff1, atrac3p_sf_huff2, atrac3p_sf_huff3,
-        atrac3p_sf_huff4, atrac3p_sf_huff5, atrac3p_sf_huff6,
-        atrac3p_sf_huff7, atrac3p_sf_huff8
-    };
-
+    xlats = atrac3p_wl_ct_xlats;
     for (int i = 0; i < 4; i++) {
-        wl_vlc_tabs[i].table = &tables_data[tab_offset];
-        wl_vlc_tabs[i].table_allocated = 1 << wl_nb_bits[i];
-        tab_offset                    += 1 << wl_nb_bits[i];
-        ff_init_vlc_from_lengths(&wl_vlc_tabs[i], wl_nb_bits[i], wl_nb_codes[i],
-                                 &wl_huffs[i][0][1], 2,
-                                 &wl_huffs[i][0][0], 2, 1,
-                                 0, INIT_VLC_USE_NEW_STATIC, NULL);
-
-        ct_vlc_tabs[i].table = &tables_data[tab_offset];
-        ct_vlc_tabs[i].table_allocated = 1 << ct_nb_bits[i];
-        tab_offset                    += 1 << ct_nb_bits[i];
-        ff_init_vlc_from_lengths(&ct_vlc_tabs[i], ct_nb_bits[i], ct_nb_codes[i],
-                                 &ct_huffs[i][0][1], 2,
-                                 &ct_huffs[i][0][0], 2, 1,
-                                 0, INIT_VLC_USE_NEW_STATIC, NULL);
+        build_canonical_huff(atrac3p_wl_cbs[i], &xlats,
+                             &tab_offset, &wl_vlc_tabs[i]);
+        build_canonical_huff(atrac3p_ct_cbs[i], &xlats,
+                             &tab_offset, &ct_vlc_tabs[i]);
     }
 
-    for (int i = 0; i < 8; i++) {
-        sf_vlc_tabs[i].table = &tables_data[tab_offset];
-        sf_vlc_tabs[i].table_allocated = 1 << sf_nb_bits[i];
-        tab_offset                    += 1 << sf_nb_bits[i];
-        ff_init_vlc_from_lengths(&sf_vlc_tabs[i], sf_nb_bits[i], sf_nb_codes[i],
-                                 &sf_huffs[i][0][1], 2,
-                                 &sf_huffs[i][0][0], 2, 1,
-                                 0, INIT_VLC_USE_NEW_STATIC, NULL);
-    }
+    xlats = atrac3p_sf_xlats;
+    for (int i = 0; i < 8; i++)
+        build_canonical_huff(atrac3p_sf_cbs[i], &xlats,
+                             &tab_offset, &sf_vlc_tabs[i]);
 
     /* build huffman tables for spectrum decoding */
     xlats = atrac3p_spectra_xlats;

diff --git a/libavcodec/atrac3plus_data.h b/libavcodec/atrac3plus_data.h
index 6b9109cb7028b105c08db5adc7dec5e71d6964bb..7039936ba3b21c6944238519fa3884b73b70d354 100644 (file)
--- a/libavcodec/atrac3plus_data.h
+++ b/libavcodec/atrac3plus_data.h
@@ -27,106 +27,83 @@
 #include <stdint.h>
 
 /** VLC tables for wordlen */
-static const uint8_t atrac3p_wl_huff1[3][2] = {
-    { 0, 1 }, { 1, 2 }, { 7, 2 },
+static const uint8_t atrac3p_wl_cbs[][12] = {
+    {  1,  2,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0 },
+    {  1,  0,  4,  0,  0,  0,  0,  0,  0,  0,  0,  0 },
+    {  1,  0,  2,  3,  2,  0,  0,  0,  0,  0,  0,  0 },
+    {  1,  0,  2,  3,  2,  0,  0,  0,  0,  0,  0,  0 },
 };
 
-static const uint8_t atrac3p_wl_huff2[5][2] = {
-    { 0, 1 }, { 1, 3 }, { 2, 3 }, { 6, 3 }, { 7, 3 },
-};
-
-static const uint8_t atrac3p_wl_huff3[8][2] = {
-    { 0, 1 }, { 1, 3 }, { 7, 3 }, { 2, 4 }, { 5, 4 }, { 6, 4 }, { 3, 5 },
-    { 4, 5 },
+/** VLC tables for code table indexes */
+static const uint8_t atrac3p_ct_cbs[][12] = {
+    {  1,  1,  2,  0,  0,  0,  0,  0,  0,  0,  0,  0 },
+    {  0,  1,  5,  2,  0,  0,  0,  0,  0,  0,  0,  0 },
+    {  0,  1,  5,  2,  0,  0,  0,  0,  0,  0,  0,  0 },
+    {  1,  0,  1,  6,  0,  0,  0,  0,  0,  0,  0,  0 },
 };
-
-static const uint8_t atrac3p_wl_huff4[8][2] = {
-    { 0, 1 }, { 1, 3 }, { 7, 3 }, { 2, 4 }, { 3, 4 }, { 6, 4 }, { 4, 5 },
-    { 5, 5 },
+/* Symbols for wordlen interleaved with symbols for code table */
+static const uint8_t atrac3p_wl_ct_xlats[] = {
+    /* wordlen table 1 - 3 entries */
+    0,  1,  7,
+    /* code table 1    - 4 entries */
+    0,  1,  2,  3,
+    /* wordlen table 2 - 5 entries */
+    0,  1,  2,  6,  7,
+    /* code table 2    - 8 entries */
+    0,  1,  2,  3,  4,  5,  6,  7,
+    /* wordlen table 3 - 8 entries */
+    0,  1,  7,  2,  5,  6,  3,  4,
+    /* code table 3    - 8 entries */
+    0,  1,  2,  3,  6,  7,  4,  5,
+    /* wordlen table 4 - 8 entries */
+    0,  1,  7,  2,  3,  6,  4,  5,
+    /* code table 4    - 8 entries */
+    0,  1,  2,  3,  4,  5,  6,  7,
 };
 
 /** VLC tables for scale factor indexes */
-static const uint8_t atrac3p_sf_huff1[64][2] = {
-    {  0,  2 }, {  1,  3 }, { 61,  3 }, { 62,  3 }, { 63,  3 }, {  2,  4 },
-    { 60,  4 }, {  3,  8 }, {  4,  8 }, {  5,  8 }, {  6,  8 }, { 57,  8 },
-    { 58,  8 }, { 59,  8 }, {  7,  9 }, {  8,  9 }, {  9,  9 }, { 10,  9 },
-    { 11,  9 }, { 12,  9 }, { 13,  9 }, { 14,  9 }, { 15,  9 }, { 16,  9 },
-    { 17,  9 }, { 18,  9 }, { 19,  9 }, { 20,  9 }, { 21,  9 }, { 22,  9 },
-    { 23,  9 }, { 24,  9 }, { 25,  9 }, { 26,  9 }, { 27,  9 }, { 28,  9 },
-    { 29,  9 }, { 30,  9 }, { 31,  9 }, { 32,  9 }, { 33,  9 }, { 34,  9 },
-    { 35,  9 }, { 36,  9 }, { 37,  9 }, { 38,  9 }, { 39,  9 }, { 40,  9 },
-    { 41,  9 }, { 42,  9 }, { 43,  9 }, { 44,  9 }, { 45,  9 }, { 46,  9 },
-    { 47,  9 }, { 48,  9 }, { 49,  9 }, { 50,  9 }, { 51,  9 }, { 52,  9 },
-    { 53,  9 }, { 54,  9 }, { 55,  9 }, { 56,  9 },
-};
-
-static const uint8_t atrac3p_sf_huff2[64][2] = {
-    {  0,  2 }, {  1,  3 }, {  2,  3 }, { 62,  3 }, { 63,  3 }, {  3,  4 },
-    { 61,  4 }, {  4,  8 }, {  5,  8 }, {  6,  8 }, { 57,  8 }, { 58,  8 },
-    { 59,  8 }, { 60,  8 }, {  7,  9 }, {  8,  9 }, {  9,  9 }, { 10,  9 },
-    { 11,  9 }, { 12,  9 }, { 13,  9 }, { 14,  9 }, { 15,  9 }, { 16,  9 },
-    { 17,  9 }, { 18,  9 }, { 19,  9 }, { 20,  9 }, { 21,  9 }, { 22,  9 },
-    { 23,  9 }, { 24,  9 }, { 25,  9 }, { 26,  9 }, { 27,  9 }, { 28,  9 },
-    { 29,  9 }, { 30,  9 }, { 31,  9 }, { 32,  9 }, { 33,  9 }, { 34,  9 },
-    { 35,  9 }, { 36,  9 }, { 37,  9 }, { 38,  9 }, { 39,  9 }, { 40,  9 },
-    { 41,  9 }, { 42,  9 }, { 43,  9 }, { 44,  9 }, { 45,  9 }, { 46,  9 },
-    { 47,  9 }, { 48,  9 }, { 49,  9 }, { 50,  9 }, { 51,  9 }, { 52,  9 },
-    { 53,  9 }, { 54,  9 }, { 55,  9 }, { 56,  9 },
-};
-
-static const uint8_t atrac3p_sf_huff3[64][2] = {
-    {  0,  1 }, {  1,  3 }, { 63,  3 }, {  2,  5 }, {  3,  5 }, { 61,  5 },
-    { 62,  5 }, {  4,  7 }, { 60,  7 }, { 59,  8 }, {  5,  9 }, {  6,  9 },
-    {  7,  9 }, {  8,  9 }, {  9,  9 }, { 10,  9 }, { 11,  9 }, { 12,  9 },
-    { 13,  9 }, { 14,  9 }, { 15,  9 }, { 16,  9 }, { 17,  9 }, { 18,  9 },
-    { 19,  9 }, { 20,  9 }, { 21,  9 }, { 22,  9 }, { 23,  9 }, { 24,  9 },
-    { 25,  9 }, { 26,  9 }, { 27,  9 }, { 28,  9 }, { 29,  9 }, { 30,  9 },
-    { 31,  9 }, { 32,  9 }, { 33,  9 }, { 34,  9 }, { 35,  9 }, { 36,  9 },
-    { 37,  9 }, { 38,  9 }, { 39,  9 }, { 40,  9 }, { 41,  9 }, { 42,  9 },
-    { 43,  9 }, { 44,  9 }, { 45,  9 }, { 46,  9 }, { 47,  9 }, { 48,  9 },
-    { 49,  9 }, { 50,  9 }, { 51,  9 }, { 52,  9 }, { 53,  9 }, { 54,  9 },
-    { 55,  9 }, { 56,  9 }, { 57,  9 }, { 58,  9 },
-};
-
-static const uint8_t atrac3p_sf_huff4[64][2] = {
-    {  0,  2 }, {  1,  3 }, {  2,  3 }, { 62,  3 }, { 63,  3 }, {  3,  5 },
-    {  4,  5 }, { 60,  5 }, { 61,  5 }, {  5,  7 }, { 58,  7 }, { 59,  7 },
-    {  6,  9 }, {  7,  9 }, {  8,  9 }, {  9,  9 }, { 10,  9 }, { 11,  9 },
-    { 12,  9 }, { 13,  9 }, { 14,  9 }, { 15,  9 }, { 16,  9 }, { 17,  9 },
-    { 18,  9 }, { 19,  9 }, { 20,  9 }, { 21,  9 }, { 22,  9 }, { 23,  9 },
-    { 24,  9 }, { 25,  9 }, { 26,  9 }, { 27,  9 }, { 28,  9 }, { 29,  9 },
-    { 30,  9 }, { 31,  9 }, { 32,  9 }, { 33,  9 }, { 34,  9 }, { 35,  9 },
-    { 36,  9 }, { 37,  9 }, { 38,  9 }, { 39,  9 }, { 40,  9 }, { 41,  9 },
-    { 42,  9 }, { 43,  9 }, { 44,  9 }, { 45,  9 }, { 46,  9 }, { 47,  9 },
-    { 48,  9 }, { 49,  9 }, { 50,  9 }, { 51,  9 }, { 52,  9 }, { 53,  9 },
-    { 54,  9 }, { 55,  9 }, { 56,  9 }, { 57,  9 },
-};
-
-static const uint8_t atrac3p_sf_huff5[15][2] = {
-    {  0,  2 }, {  1,  3 }, { 13,  3 }, { 14,  3 }, { 15,  3 }, {  2,  4 },
-    { 12,  4 }, {  3,  6 }, {  4,  6 }, {  5,  6 }, {  6,  6 }, {  7,  6 },
-    {  9,  6 }, { 10,  6 }, { 11,  6 },
+static const uint8_t atrac3p_sf_cbs[][12] = {
+    {  0,  1,  4,  2,  0,  0,  0,  7, 50,  0,  0,  0 },
+    {  0,  1,  4,  2,  0,  0,  0,  7, 50,  0,  0,  0 },
+    {  1,  0,  2,  0,  4,  0,  2,  1, 54,  0,  0,  0 },
+    {  0,  1,  4,  0,  4,  0,  3,  0, 52,  0,  0,  0 },
+    {  0,  1,  4,  2,  0,  8,  0,  0,  0,  0,  0,  0 },
+    {  0,  1,  4,  2,  0,  8,  0,  0,  0,  0,  0,  0 },
+    {  1,  0,  2,  2,  2,  0,  8,  0,  0,  0,  0,  0 },
+    {  0,  1,  4,  2,  2,  2,  4,  0,  0,  0,  0,  0 },
 };
 
-static const uint8_t atrac3p_sf_huff6[15][2] = {
-    {  0,  2 }, {  1,  3 }, {  2,  3 }, { 14,  3 }, { 15,  3 }, {  3,  4 },
-    { 13,  4 }, {  4,  6 }, {  5,  6 }, {  6,  6 }, {  7,  6 }, {  9,  6 },
-    { 10,  6 }, { 11,  6 }, { 12,  6 },
+static const uint8_t atrac3p_sf_xlats[] = {
+    /* Scale factor index 1 - 64 entries */
+     0,  1, 61, 62, 63,  2, 60,  3,  4,  5,  6, 57, 58, 59,  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,
+    /* Scale factor index 2 - 64 entries */
+     0,  1,  2, 62, 63,  3, 61,  4,  5,  6, 57, 58, 59, 60,  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,
+    /* Scale factor index 3 - 64 entries */
+     0,  1, 63,  2,  3, 61, 62,  4, 60, 59,  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,
+    /* Scale factor index 4 - 64 entries */
+     0,  1,  2, 62, 63,  3,  4, 60, 61,  5, 58, 59,  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,
+    /* Scale factor index 5 - 15 entries */
+     0,  1, 13, 14, 15,  2, 12,  3,  4,  5,  6,  7,  9, 10, 11,
+    /* Scale factor index 6 - 15 entries */
+     0,  1,  2, 14, 15,  3, 13,  4,  5,  6,  7,  9, 10, 11, 12,
+    /* Scale factor index 7 - 15 entries */
+     0,  1, 15,  2, 14,  3, 13,  4,  5,  6,  7,  9, 10, 11, 12,
+    /* Scale factor index 8 - 15 entries */
+     0,  1,  2, 14, 15,  3, 13,  4, 12,  5, 11,  6,  7,  9, 10,
 };
 
-static const uint8_t atrac3p_sf_huff7[15][2] = {
-    {  0,  1 }, {  1,  3 }, { 15,  3 }, {  2,  4 }, { 14,  4 }, {  3,  5 },
-    { 13,  5 }, {  4,  7 }, {  5,  7 }, {  6,  7 }, {  7,  7 }, {  9,  7 },
-    { 10,  7 }, { 11,  7 }, { 12,  7 },
-};
-
-static const uint8_t atrac3p_sf_huff8[15][2] = {
-    {  0,  2 }, {  1,  3 }, {  2,  3 }, { 14,  3 }, { 15,  3 }, {  3,  4 },
-    { 13,  4 }, {  4,  5 }, { 12,  5 }, {  5,  6 }, { 11,  6 }, {  6,  7 },
-    {  7,  7 }, {  9,  7 }, { 10,  7 },
-};
-
-/** VLC tables for code table indexes */
 static const uint8_t atrac3p_ct_huff1[4][2] = {
     { 0, 1 }, { 1, 2 }, { 2, 3 }, { 3, 3 },
 };