1 files changed, 205 insertions, 116 deletions

diff --git a/apps/codecs/lib/ffmpeg_bitstream.c b/apps/codecs/lib/ffmpeg_bitstream.c
index 88e3cbfe3a..c879661c47 100644
--- a/apps/codecs/lib/ffmpeg_bitstream.c
+++ b/apps/codecs/lib/ffmpeg_bitstream.c
@@ -2,6 +2,7 @@
  * Common bit i/o utils
  * Copyright (c) 2000, 2001 Fabrice Bellard
  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2010 Loren Merritt
  *
  * alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
  *
@@ -22,7 +23,16 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "ffmpeg_bitstream.h"
+/**
+ * @file
+ * bitstream api.
+ */
+
+//#include "avcodec.h"
+#include "ffmpeg_get_bits.h"
+//#include "put_bits.h"
+
+#define av_log(...)
 
 #ifdef ROCKBOX
 #undef DEBUGF
@@ -36,27 +46,47 @@ const uint8_t ff_log2_run[32]={
  8, 9,10,11,12,13,14,15
 };
 
-/**
- * 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/misdesigned
- * and should correctly use static arrays
- */
-
+#if 0 // unused in rockbox
+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, const char *s, int put_zero)
+void ff_put_string(PutBitContext *pb, const char *string, int terminate_string)
 {
-    while(*s){
-        put_bits(pbc, 8, *s);
-        s++;
+    while(*string){
+        put_bits(pb, 8, *string);
+        string++;
     }
-    if(put_zero)
-        put_bits(pbc, 8, 0);
+    if(terminate_string)
+        put_bits(pb, 8, 0);
 }
 
+void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length)
+{
+    int words= length>>4;
+    int bits= length&15;
+    int i;
+
+    if(length==0) return;
+
+    if(CONFIG_SMALL || words < 16 || put_bits_count(pb)&7){
+        for(i=0; i<words; i++) put_bits(pb, 16, AV_RB16(src + 2*i));
+    }else{
+        for(i=0; put_bits_count(pb)&31; i++)
+            put_bits(pb, 8, src[i]);
+        flush_put_bits(pb);
+        memcpy(put_bits_ptr(pb), src+i, 2*words-i);
+        skip_put_bytes(pb, 2*words-i);
+    }
+
+    put_bits(pb, bits, AV_RB16(src + 2*words)>>(16-bits));
+}
+#endif
 /* VLC decoding */
 
 //#define DEBUG_VLC
@@ -84,118 +114,143 @@ static int alloc_table(VLC *vlc, int size, int use_static)
     index = vlc->table_size;
     vlc->table_size += size;
     if (vlc->table_size > vlc->table_allocated) {
-        if(use_static>1){
+        if(use_static)
+        {
             DEBUGF("init_vlc() used with too little memory : table_size > allocated_memory\n");
+            return -1;
         }
-
+//            abort(); //cant do anything, init_vlc() is used with too little memory
+//        vlc->table_allocated += (1 << vlc->bits);
+//        vlc->table = av_realloc(vlc->table,
+//                                sizeof(VLC_TYPE) * 2 * vlc->table_allocated);
         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,
-                       const void *symbols, int symbols_wrap, int symbols_size,
-                       uint32_t code_prefix, int n_prefix, int flags)
-{
-    int i, j, k, n, table_size, table_index, nb, n1, index, code_prefix2, symbol;
+/* 
+static av_always_inline uint32_t bitswap_32(uint32_t x) {
+    return av_reverse[x&0xFF]<<24
+         | av_reverse[(x>>8)&0xFF]<<16
+         | av_reverse[(x>>16)&0xFF]<<8
+         | av_reverse[x>>24];
+}
+*/
+
+typedef struct {
+    uint8_t bits;
+    uint16_t symbol;
+    /** codeword, with the first bit-to-be-read in the msb
+     * (even if intended for a little-endian bitstream reader) */
     uint32_t code;
+} VLCcode;
+
+static int compare_vlcspec(const void *a, const void *b)
+{
+    const VLCcode *sa=a, *sb=b;
+    return (sa->code >> 1) - (sb->code >> 1);
+}
+
+/**
+ * Build VLC decoding tables suitable for use with get_vlc().
+ *
+ * @param vlc            the context to be initted
+ *
+ * @param table_nb_bits  max length of vlc codes to store directly in this table
+ *                       (Longer codes are delegated to subtables.)
+ *
+ * @param nb_codes       number of elements in codes[]
+ *
+ * @param codes          descriptions of the vlc codes
+ *                       These must be ordered such that codes going into the same subtable are contiguous.
+ *                       Sorting by VLCcode.code is sufficient, though not necessary.
+ */
+static int build_table(VLC *vlc, int table_nb_bits, int nb_codes,
+                       VLCcode *codes, int flags)
+{
+    int table_size, table_index, index, symbol, subtable_bits;
+    int i, j, k, n, nb, inc;
+    uint32_t code, code_prefix;
     VLC_TYPE (*table)[2];
 
     table_size = 1 << table_nb_bits;
-    table_index = alloc_table(vlc, table_size, flags & (INIT_VLC_USE_STATIC|INIT_VLC_USE_NEW_STATIC));
+    table_index = alloc_table(vlc, table_size, flags & INIT_VLC_USE_NEW_STATIC);
 #ifdef DEBUG_VLC
-    DEBUGF("new table index=%d size=%d code_prefix=%x n=%d\n",
-           table_index, table_size, code_prefix, n_prefix);
+    av_log(NULL,AV_LOG_DEBUG,"new table index=%d size=%d\n",
+           table_index, table_size);
 #endif
     if (table_index < 0)
         return -1;
     table = &vlc->table[table_index];
 
-    for(i=0;i<table_size;i++) {
+    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 (!symbols)
-            symbol = i;
-        else
-            GET_DATA(symbol, symbols, i, symbols_wrap, symbols_size);
+    for (i = 0; i < nb_codes; i++) {
+        n = codes[i].bits;
+        code = codes[i].code;
+        symbol = codes[i].symbol;
 #if defined(DEBUG_VLC) && 0
-        DEBUGF("i=%d n=%d code=0x%x\n", i, n, code);
+        av_log(NULL,AV_LOG_DEBUG,"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 ? (int)0xffffffff : (1 << n_prefix)-1);
-        else
-            code_prefix2= code >> n;
-        if (n > 0 && code_prefix2 == (int)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);
+        if (n <= table_nb_bits) {
+            /* no need to add another table */
+            j = code >> (32 - table_nb_bits);
+            nb = 1 << (table_nb_bits - n);
+            inc = 1;
+/*            if (flags & INIT_VLC_LE) {
+                j = bitswap_32(code);
+                inc = 1 << n;
+            } */
+            for (k = 0; k < nb; k++) {
 #ifdef DEBUG_VLC
-                    DEBUGF("%4x: code=%d n=%d\n",
-                           j, i, n);
+                av_log(NULL, AV_LOG_DEBUG, "%4x: code=%d n=%d\n",
+                       j, i, n);
 #endif
-                    if (table[j][1] /*bits*/ != 0) {
-                        DEBUGF("incorrect codes\n");
-                        return -1;
-                    }
-                    table[j][1] = n; //bits
-                    table[j][0] = symbol;
-                    j++;
+                if (table[j][1] /*bits*/ != 0) {
+                    av_log(NULL, AV_LOG_ERROR, "incorrect codes\n");
+                    return -1;
                 }
-            } else {
-                n -= table_nb_bits;
-                j = (code >> ((flags & INIT_VLC_LE) ? n_prefix : n)) & ((1 << table_nb_bits) - 1);
-#ifdef DEBUG_VLC
-                DEBUGF("%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
+                table[j][1] = n; //bits
+                table[j][0] = symbol;
+                j += inc;
             }
-        }
-    }
-
-    /* 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
+        } else {
+            /* fill auxiliary table recursively */
+            n -= table_nb_bits;
+            code_prefix = code >> (32 - table_nb_bits);
+            subtable_bits = n;
+            codes[i].bits = n;
+            codes[i].code = code << table_nb_bits;
+            for (k = i+1; k < nb_codes; k++) {
+                n = codes[k].bits - table_nb_bits;
+                if (n <= 0)
+                    break;
+                code = codes[k].code;
+                if (code >> (32 - table_nb_bits) != code_prefix)
+                    break;
+                codes[k].bits = n;
+                codes[k].code = code << table_nb_bits;
+                subtable_bits = FFMAX(subtable_bits, n);
             }
-            index = build_table(vlc, n, nb_codes,
-                                bits, bits_wrap, bits_size,
-                                codes, codes_wrap, codes_size,
-                                symbols, symbols_wrap, symbols_size,
-                                (flags & INIT_VLC_LE) ? (code_prefix | (i << n_prefix)) : ((code_prefix << table_nb_bits) | i),
-                                n_prefix + table_nb_bits, flags);
+            subtable_bits = FFMIN(subtable_bits, table_nb_bits);
+            j = /*(flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) :*/ code_prefix;
+            table[j][1] = -subtable_bits;
+#ifdef DEBUG_VLC
+            av_log(NULL,AV_LOG_DEBUG,"%4x: n=%d (subtable)\n",
+                   j, codes[i].bits + table_nb_bits);
+#endif
+            index = build_table(vlc, subtable_bits, k-i, codes+i, flags);
             if (index < 0)
                 return -1;
             /* note: realloc has been done, so reload tables */
             table = &vlc->table[table_index];
-            table[i][0] = index; //code
+            table[j][0] = index; //code
+            i = k-1;
         }
     }
     return table_index;
@@ -228,49 +283,83 @@ static int build_table(VLC *vlc, int table_nb_bits,
    'use_static' should be set to 1 for tables, which should be freed
    with av_free_static(), 0 if free_vlc() will be used.
 */
+
+/* Rockbox: support for INIT_VLC_LE is currently disabled since none of our
+   codecs use it, there's a LUT based bit reverse function for this commented
+   out above (bitswap_32) and an inline asm version in libtremor/codebook.c
+   if we ever want this */
 int init_vlc_sparse(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,
              const void *symbols, int symbols_wrap, int symbols_size,
              int flags)
 {
+    VLCcode buf[nb_codes+1]; /* worst case from cook seems to be nb_codes == 607
+                                which would make this about 4.8k... */
+    int i, j, ret;
+
     vlc->bits = nb_bits;
     if(flags & INIT_VLC_USE_NEW_STATIC){
         if(vlc->table_size && vlc->table_size == vlc->table_allocated){
             return 0;
         }else if(vlc->table_size){
-            return -1; // fatal error, we are called on a partially initialized table
+            DEBUGF("fatal error, we are called on a partially initialized table\n");
+            return -1;
+//            abort(); // fatal error, we are called on a partially initialized table
         }
-    }else if(!(flags & INIT_VLC_USE_STATIC)) {
+    }else {
         vlc->table = NULL;
         vlc->table_allocated = 0;
         vlc->table_size = 0;
-    } else {
-        /* Static tables are initially always NULL, return
-           if vlc->table != NULL to avoid double allocation */
-        if(vlc->table)
-            return 0;
     }
 
 #ifdef DEBUG_VLC
-    DEBUGF("build table nb_codes=%d\n", nb_codes);
+    av_log(NULL,AV_LOG_DEBUG,"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,
-                    symbols, symbols_wrap, symbols_size,
-                    0, 0, flags) < 0) {
-        //free(&vlc->table);
+//    buf = av_malloc((nb_codes+1)*sizeof(VLCcode));
+
+//    assert(symbols_size <= 2 || !symbols);
+    j = 0;
+#define COPY(condition)\
+    for (i = 0; i < nb_codes; i++) {\
+        GET_DATA(buf[j].bits, bits, i, bits_wrap, bits_size);\
+        if (!(condition))\
+            continue;\
+        GET_DATA(buf[j].code, codes, i, codes_wrap, codes_size);\
+/*        if (flags & INIT_VLC_LE)*/\
+/*            buf[j].code = bitswap_32(buf[j].code);*/\
+/*        else*/\
+            buf[j].code <<= 32 - buf[j].bits;\
+        if (symbols)\
+            GET_DATA(buf[j].symbol, symbols, i, symbols_wrap, symbols_size)\
+        else\
+            buf[j].symbol = i;\
+        j++;\
+    }
+    COPY(buf[j].bits > nb_bits);
+    // qsort is the slowest part of init_vlc, and could probably be improved or avoided
+    qsort(buf, j, sizeof(VLCcode), compare_vlcspec);
+    COPY(buf[j].bits && buf[j].bits <= nb_bits);
+    nb_codes = j;
+
+    ret = build_table(vlc, nb_bits, nb_codes, buf, flags);
+
+//    av_free(buf);
+    if (ret < 0) {
+//        av_freep(&vlc->table);
         return -1;
     }
-    /* Changed the following condition to be true if table_size > table_allocated. *
-     * This would be more sensible for static tables since we want warnings for    *
-     * memory shortages only.                                                      */
-#ifdef TEST
-    if((flags & INIT_VLC_USE_NEW_STATIC) && vlc->table_size > vlc->table_allocated)
-        DEBUGF("needed %d had %d\n", vlc->table_size, vlc->table_allocated);
-#endif
+    if((flags & INIT_VLC_USE_NEW_STATIC) && vlc->table_size != vlc->table_allocated) {
+        av_log(NULL, AV_LOG_ERROR, "needed %d had %d\n", vlc->table_size, vlc->table_allocated);
+    }
     return 0;
 }
 
+/* not used in rockbox
+void free_vlc(VLC *vlc)
+{
+    av_freep(&vlc->table);
+}
+*/
+