1 /*
2  * Copyright (c) 2016, Alliance for Open Media. All rights reserved
3  *
4  * This source code is subject to the terms of the BSD 2 Clause License and
5  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6  * was not distributed with this source code in the LICENSE file, you can
7  * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8  * Media Patent License 1.0 was not distributed with this source code in the
9  * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
10  */
11 
12 #include <assert.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 
17 #include "aom/aom_integer.h"
18 #include "av1/decoder/accounting.h"
19 
accounting_hash(const char * str)20 static int accounting_hash(const char *str) {
21   uint32_t val;
22   const unsigned char *ustr;
23   val = 0;
24   ustr = (const unsigned char *)str;
25   /* This is about the worst hash one can design, but it should be good enough
26      here. */
27   while (*ustr) val += *ustr++;
28   return val % AOM_ACCOUNTING_HASH_SIZE;
29 }
30 
31 /* Dictionary lookup based on an open-addressing hash table. */
aom_accounting_dictionary_lookup(Accounting * accounting,const char * str)32 int aom_accounting_dictionary_lookup(Accounting *accounting, const char *str) {
33   int hash;
34   size_t len;
35   AccountingDictionary *dictionary;
36   dictionary = &accounting->syms.dictionary;
37   hash = accounting_hash(str);
38   while (accounting->hash_dictionary[hash] != -1) {
39     if (strcmp(dictionary->strs[accounting->hash_dictionary[hash]], str) == 0) {
40       return accounting->hash_dictionary[hash];
41     }
42     hash++;
43     if (hash == AOM_ACCOUNTING_HASH_SIZE) hash = 0;
44   }
45   /* No match found. */
46   assert(dictionary->num_strs + 1 < MAX_SYMBOL_TYPES);
47   accounting->hash_dictionary[hash] = dictionary->num_strs;
48   len = strlen(str);
49   dictionary->strs[dictionary->num_strs] = malloc(len + 1);
50   snprintf(dictionary->strs[dictionary->num_strs], len + 1, "%s", str);
51   dictionary->num_strs++;
52   return dictionary->num_strs - 1;
53 }
54 
aom_accounting_init(Accounting * accounting)55 void aom_accounting_init(Accounting *accounting) {
56   int i;
57   accounting->num_syms_allocated = 1000;
58   accounting->syms.syms =
59       malloc(sizeof(AccountingSymbol) * accounting->num_syms_allocated);
60   accounting->syms.dictionary.num_strs = 0;
61   assert(AOM_ACCOUNTING_HASH_SIZE > 2 * MAX_SYMBOL_TYPES);
62   for (i = 0; i < AOM_ACCOUNTING_HASH_SIZE; i++)
63     accounting->hash_dictionary[i] = -1;
64   aom_accounting_reset(accounting);
65 }
66 
aom_accounting_reset(Accounting * accounting)67 void aom_accounting_reset(Accounting *accounting) {
68   accounting->syms.num_syms = 0;
69   accounting->syms.num_binary_syms = 0;
70   accounting->syms.num_multi_syms = 0;
71   accounting->context.x = -1;
72   accounting->context.y = -1;
73   accounting->last_tell_frac = 0;
74 }
75 
aom_accounting_clear(Accounting * accounting)76 void aom_accounting_clear(Accounting *accounting) {
77   int i;
78   AccountingDictionary *dictionary;
79   free(accounting->syms.syms);
80   dictionary = &accounting->syms.dictionary;
81   for (i = 0; i < dictionary->num_strs; i++) {
82     free(dictionary->strs[i]);
83   }
84 }
85 
aom_accounting_set_context(Accounting * accounting,int16_t x,int16_t y)86 void aom_accounting_set_context(Accounting *accounting, int16_t x, int16_t y) {
87   accounting->context.x = x;
88   accounting->context.y = y;
89 }
90 
aom_accounting_record(Accounting * accounting,const char * str,uint32_t bits)91 void aom_accounting_record(Accounting *accounting, const char *str,
92                            uint32_t bits) {
93   AccountingSymbol sym;
94   // Reuse previous symbol if it has the same context and symbol id.
95   if (accounting->syms.num_syms) {
96     AccountingSymbol *last_sym;
97     last_sym = &accounting->syms.syms[accounting->syms.num_syms - 1];
98     if (memcmp(&last_sym->context, &accounting->context,
99                sizeof(AccountingSymbolContext)) == 0) {
100       uint32_t id;
101       id = aom_accounting_dictionary_lookup(accounting, str);
102       if (id == last_sym->id) {
103         last_sym->bits += bits;
104         last_sym->samples++;
105         return;
106       }
107     }
108   }
109   sym.context = accounting->context;
110   sym.samples = 1;
111   sym.bits = bits;
112   sym.id = aom_accounting_dictionary_lookup(accounting, str);
113   assert(sym.id <= 255);
114   if (accounting->syms.num_syms == accounting->num_syms_allocated) {
115     accounting->num_syms_allocated *= 2;
116     accounting->syms.syms =
117         realloc(accounting->syms.syms,
118                 sizeof(AccountingSymbol) * accounting->num_syms_allocated);
119     assert(accounting->syms.syms != NULL);
120   }
121   accounting->syms.syms[accounting->syms.num_syms++] = sym;
122 }
123 
aom_accounting_dump(Accounting * accounting)124 void aom_accounting_dump(Accounting *accounting) {
125   int i;
126   AccountingSymbol *sym;
127   printf("\n----- Number of recorded syntax elements = %d -----\n",
128          accounting->syms.num_syms);
129   printf("----- Total number of symbol calls = %d (%d binary) -----\n",
130          accounting->syms.num_multi_syms + accounting->syms.num_binary_syms,
131          accounting->syms.num_binary_syms);
132   for (i = 0; i < accounting->syms.num_syms; i++) {
133     sym = &accounting->syms.syms[i];
134     printf("%s x: %d, y: %d bits: %f samples: %d\n",
135            accounting->syms.dictionary.strs[sym->id], sym->context.x,
136            sym->context.y, (float)sym->bits / 8.0, sym->samples);
137   }
138 }
139