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authorMichael Giacomelli <giac2000@hotmail.com>2007-07-12 03:17:19 +0000
committerMichael Giacomelli <giac2000@hotmail.com>2007-07-12 03:17:19 +0000
commit362f894a53c137439d57d049780aa1ae1203a887 (patch)
treeffa39b4d2e094b5e5eef72fb8ba94ea66b21db77 /apps/codecs/libwma/bitstream.c
parenta9df713ee9c9bbae872ad5364f037e5993e5be88 (diff)
downloadrockbox-362f894a53c137439d57d049780aa1ae1203a887.tar.gz
rockbox-362f894a53c137439d57d049780aa1ae1203a887.zip
Sync the bitstream functions with ffmpeg. Switch wmadeci.c over to get_vlc2 which is how ffmpeg now does it and is also slightly faster. Add in defines for later VLC memory usage optization. Kill some header files that weren't needed and update others that were out of sync. We're now much closer to the current ffmpeg codec which should make fixing the remaining issues much easier.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@13859 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/codecs/libwma/bitstream.c')
-rw-r--r--apps/codecs/libwma/bitstream.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/apps/codecs/libwma/bitstream.c b/apps/codecs/libwma/bitstream.c
new file mode 100644
index 0000000000..12cf0518ee
--- /dev/null
+++ b/apps/codecs/libwma/bitstream.c
@@ -0,0 +1,274 @@
+/*
+ * Common bit i/o utils
+ * Copyright (c) 2000, 2001 Fabrice Bellard.
+ * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
+ */
+
+/**
+ * @file bitstream.c
+ * bitstream api.
+ */
+
+#include "bitstream.h"
+
+/**
+ * Same as av_mallocz_static(), but does a realloc.
+ *
+ * @param[in] ptr The block of memory to reallocate.
+ * @param[in] size The requested size.
+ * @return Block of memory of requested size.
+ * @deprecated. Code which uses ff_realloc_static is broken/missdesigned
+ * and should correctly use static arrays
+ */
+attribute_deprecated void *ff_realloc_static(void *ptr, unsigned int size);
+
+
+const uint8_t ff_sqrt_tab[128]={
+ 0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 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, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,11
+};
+
+const uint8_t ff_log2_tab[256]={
+ 0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+ 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
+};
+
+
+void align_put_bits(PutBitContext *s)
+{
+#ifdef ALT_BITSTREAM_WRITER
+ put_bits(s,( - s->index) & 7,0);
+#else
+ put_bits(s,s->bit_left & 7,0);
+#endif
+}
+
+void ff_put_string(PutBitContext * pbc, char *s, int put_zero)
+{
+ while(*s){
+ put_bits(pbc, 8, *s);
+ s++;
+ }
+ if(put_zero)
+ put_bits(pbc, 8, 0);
+}
+
+/* VLC decoding */
+
+//#define DEBUG_VLC
+
+#define GET_DATA(v, table, i, wrap, size) \
+{\
+ const uint8_t *ptr = (const uint8_t *)table + i * wrap;\
+ switch(size) {\
+ case 1:\
+ v = *(const uint8_t *)ptr;\
+ break;\
+ case 2:\
+ v = *(const uint16_t *)ptr;\
+ break;\
+ default:\
+ v = *(const uint32_t *)ptr;\
+ break;\
+ }\
+}
+
+
+static int alloc_table(VLC *vlc, int size)
+{
+ int index;
+ index = vlc->table_size;
+ vlc->table_size += size;
+ if (vlc->table_size > vlc->table_allocated) {
+ vlc->table_allocated += (1 << vlc->bits);
+ if (!vlc->table)
+ return -1;
+ }
+ return index;
+}
+
+static int build_table(VLC *vlc, int table_nb_bits,
+ int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ uint32_t code_prefix, int n_prefix)
+{
+ int i, j, k, n, table_size, table_index, nb, n1, index, code_prefix2;
+ uint32_t code;
+ int flags = 0;
+ VLC_TYPE (*table)[2];
+
+ table_size = 1 << table_nb_bits;
+ table_index = alloc_table(vlc, table_size);
+#ifdef DEBUG_VLC
+ printf("new table index=%d size=%d code_prefix=%x n=%d\n",
+ table_index, table_size, code_prefix, n_prefix);
+#endif
+ if (table_index < 0)
+ return -1;
+ table = &vlc->table[table_index];
+
+ for(i=0;i<table_size;i++) {
+ table[i][1] = 0; //bits
+ table[i][0] = -1; //codes
+ }
+
+ /* first pass: map codes and compute auxillary table sizes */
+ for(i=0;i<nb_codes;i++) {
+ GET_DATA(n, bits, i, bits_wrap, bits_size);
+ GET_DATA(code, codes, i, codes_wrap, codes_size);
+ /* we accept tables with holes */
+ if (n <= 0)
+ continue;
+#if defined(DEBUG_VLC) && 0
+ printf("i=%d n=%d code=0x%x\n", i, n, code);
+#endif
+ /* if code matches the prefix, it is in the table */
+ n -= n_prefix;
+ if(flags & INIT_VLC_LE)
+ code_prefix2= code & (n_prefix>=32 ? 0xffffffff : (1 << n_prefix)-1);
+ else
+ code_prefix2= code >> n;
+ if (n > 0 && code_prefix2 == code_prefix) {
+ if (n <= table_nb_bits) {
+ /* no need to add another table */
+ j = (code << (table_nb_bits - n)) & (table_size - 1);
+ nb = 1 << (table_nb_bits - n);
+ for(k=0;k<nb;k++) {
+ if(flags & INIT_VLC_LE)
+ j = (code >> n_prefix) + (k<<n);
+#ifdef DEBUG_VLC
+ av_log(NULL, AV_LOG_DEBUG, "%4x: code=%d n=%d\n",
+ j, i, n);
+#endif
+ if (table[j][1] /*bits*/ != 0) {
+ // av_log(NULL, AV_LOG_ERROR, "incorrect codes\n");
+ return -1;
+ }
+ table[j][1] = n; //bits
+ table[j][0] = i; //code
+ j++;
+ }
+ } else {
+ n -= table_nb_bits;
+ j = (code >> ((flags & INIT_VLC_LE) ? n_prefix : n)) & ((1 << table_nb_bits) - 1);
+#ifdef DEBUG_VLC
+ printf("%4x: n=%d (subtable)\n",
+ j, n);
+#endif
+ /* compute table size */
+ n1 = -table[j][1]; //bits
+ if (n > n1)
+ n1 = n;
+ table[j][1] = -n1; //bits
+ }
+ }
+ }
+
+ /* second pass : fill auxillary tables recursively */
+ for(i=0;i<table_size;i++) {
+ n = table[i][1]; //bits
+ if (n < 0) {
+ n = -n;
+ if (n > table_nb_bits) {
+ n = table_nb_bits;
+ table[i][1] = -n; //bits
+ }
+ index = build_table(vlc, n, nb_codes,
+ bits, bits_wrap, bits_size,
+ codes, codes_wrap, codes_size,
+ (flags & INIT_VLC_LE) ? (code_prefix | (i << n_prefix)) : ((code_prefix << table_nb_bits) | i),
+ n_prefix + table_nb_bits);
+ if (index < 0)
+ return -1;
+ /* note: realloc has been done, so reload tables */
+ table = &vlc->table[table_index];
+ table[i][0] = index; //code
+ }
+ }
+ return table_index;
+}
+
+
+/* Build VLC decoding tables suitable for use with get_vlc().
+
+ 'nb_bits' set thee decoding table size (2^nb_bits) entries. The
+ bigger it is, the faster is the decoding. But it should not be too
+ big to save memory and L1 cache. '9' is a good compromise.
+
+ 'nb_codes' : number of vlcs codes
+
+ 'bits' : table which gives the size (in bits) of each vlc code.
+
+ 'codes' : table which gives the bit pattern of of each vlc code.
+
+ 'xxx_wrap' : give the number of bytes between each entry of the
+ 'bits' or 'codes' tables.
+
+ 'xxx_size' : gives the number of bytes of each entry of the 'bits'
+ or 'codes' tables.
+
+ 'wrap' and 'size' allows to use any memory configuration and types
+ (byte/word/long) to store the 'bits' and 'codes' tables.
+
+ 'use_static' should be set to 1 for tables, which should be freed
+ with av_free_static(), 0 if free_vlc() will be used.
+*/
+int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ int flags)
+{
+
+ vlc->bits = nb_bits;
+ vlc->table_size = 0;
+
+#ifdef DEBUG_VLC
+ printf("build table nb_codes=%d\n", nb_codes);
+#endif
+
+ if (build_table(vlc, nb_bits, nb_codes,
+ bits, bits_wrap, bits_size,
+ codes, codes_wrap, codes_size,
+ 0, 0) < 0) {
+ //av_free(vlc->table);
+ return -1;
+ }
+ /* return flags to block gcc warning while allowing us to keep
+ * consistent with ffmpeg's function parameters
+ */
+ return flags;
+}
+
+/*
+void free_vlc(VLC *vlc)
+{
+ av_free(vlc->table);
+}
+*/