Set default qmax for VC-3/DNxHD to 1024 (maximum allowed by VC-3 spec).
[ffmpeg.git] / libavcodec / bytestream.h
1 /*
2  * Bytestream functions
3  * copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@free.fr>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21
22 #ifndef AVCODEC_BYTESTREAM_H
23 #define AVCODEC_BYTESTREAM_H
24
25 #include <string.h>
26 #include "libavutil/common.h"
27 #include "libavutil/intreadwrite.h"
28
29 typedef struct {
30     const uint8_t *buffer, *buffer_end, *buffer_start;
31 } GetByteContext;
32
33 #define DEF_T(type, name, bytes, read, write)                             \
34 static av_always_inline type bytestream_get_ ## name(const uint8_t **b){\
35     (*b) += bytes;\
36     return read(*b - bytes);\
37 }\
38 static av_always_inline void bytestream_put_ ##name(uint8_t **b, const type value){\
39     write(*b, value);\
40     (*b) += bytes;\
41 }\
42 static av_always_inline type bytestream2_get_ ## name ## u(GetByteContext *g)\
43 {\
44     return bytestream_get_ ## name(&g->buffer);\
45 }\
46 static av_always_inline type bytestream2_get_ ## name(GetByteContext *g)\
47 {\
48     if (g->buffer_end - g->buffer < bytes)\
49         return 0;\
50     return bytestream2_get_ ## name ## u(g);\
51 }\
52 static av_always_inline type bytestream2_peek_ ## name(GetByteContext *g)\
53 {\
54     if (g->buffer_end - g->buffer < bytes)\
55         return 0;\
56     return read(g->buffer);\
57 }
58
59 #define DEF(name, bytes, read, write) \
60     DEF_T(unsigned int, name, bytes, read, write)
61 #define DEF64(name, bytes, read, write) \
62     DEF_T(uint64_t, name, bytes, read, write)
63
64 DEF64(le64, 8, AV_RL64, AV_WL64)
65 DEF  (le32, 4, AV_RL32, AV_WL32)
66 DEF  (le24, 3, AV_RL24, AV_WL24)
67 DEF  (le16, 2, AV_RL16, AV_WL16)
68 DEF64(be64, 8, AV_RB64, AV_WB64)
69 DEF  (be32, 4, AV_RB32, AV_WB32)
70 DEF  (be24, 3, AV_RB24, AV_WB24)
71 DEF  (be16, 2, AV_RB16, AV_WB16)
72 DEF  (byte, 1, AV_RB8 , AV_WB8 )
73
74 #undef DEF
75 #undef DEF64
76 #undef DEF_T
77
78 #if HAVE_BIGENDIAN
79 #   define bytestream2_get_ne16  bytestream2_get_be16
80 #   define bytestream2_get_ne24  bytestream2_get_be24
81 #   define bytestream2_get_ne32  bytestream2_get_be32
82 #   define bytestream2_get_ne64  bytestream2_get_be64
83 #   define bytestream2_get_ne16u bytestream2_get_be16u
84 #   define bytestream2_get_ne24u bytestream2_get_be24u
85 #   define bytestream2_get_ne32u bytestream2_get_be32u
86 #   define bytestream2_get_ne64u bytestream2_get_be64u
87 #   define bytestream2_put_ne16  bytestream2_put_be16
88 #   define bytestream2_put_ne24  bytestream2_put_be24
89 #   define bytestream2_put_ne32  bytestream2_put_be32
90 #   define bytestream2_put_ne64  bytestream2_put_be64
91 #   define bytestream2_peek_ne16 bytestream2_peek_be16
92 #   define bytestream2_peek_ne24 bytestream2_peek_be24
93 #   define bytestream2_peek_ne32 bytestream2_peek_be32
94 #   define bytestream2_peek_ne64 bytestream2_peek_be64
95 #else
96 #   define bytestream2_get_ne16  bytestream2_get_le16
97 #   define bytestream2_get_ne24  bytestream2_get_le24
98 #   define bytestream2_get_ne32  bytestream2_get_le32
99 #   define bytestream2_get_ne64  bytestream2_get_le64
100 #   define bytestream2_get_ne16u bytestream2_get_le16u
101 #   define bytestream2_get_ne24u bytestream2_get_le24u
102 #   define bytestream2_get_ne32u bytestream2_get_le32u
103 #   define bytestream2_get_ne64u bytestream2_get_le64u
104 #   define bytestream2_put_ne16  bytestream2_put_le16
105 #   define bytestream2_put_ne24  bytestream2_put_le24
106 #   define bytestream2_put_ne32  bytestream2_put_le32
107 #   define bytestream2_put_ne64  bytestream2_put_le64
108 #   define bytestream2_peek_ne16 bytestream2_peek_le16
109 #   define bytestream2_peek_ne24 bytestream2_peek_le24
110 #   define bytestream2_peek_ne32 bytestream2_peek_le32
111 #   define bytestream2_peek_ne64 bytestream2_peek_le64
112 #endif
113
114 static av_always_inline void bytestream2_init(GetByteContext *g,
115                                               const uint8_t *buf, int buf_size)
116 {
117     g->buffer =  buf;
118     g->buffer_start = buf;
119     g->buffer_end = buf + buf_size;
120 }
121
122 static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
123 {
124     return g->buffer_end - g->buffer;
125 }
126
127 static av_always_inline void bytestream2_skip(GetByteContext *g,
128                                               unsigned int size)
129 {
130     g->buffer += FFMIN(g->buffer_end - g->buffer, size);
131 }
132
133 static av_always_inline int bytestream2_tell(GetByteContext *g)
134 {
135     return (int)(g->buffer - g->buffer_start);
136 }
137
138 static av_always_inline int bytestream2_seek(GetByteContext *g, int offset,
139                                              int whence)
140 {
141     switch (whence) {
142     case SEEK_CUR:
143         offset = av_clip(offset, -(g->buffer - g->buffer_start),
144                          g->buffer_end - g->buffer);
145         g->buffer += offset;
146         break;
147     case SEEK_END:
148         offset = av_clip(offset, -(g->buffer_end - g->buffer_start), 0);
149         g->buffer = g->buffer_end + offset;
150         break;
151     case SEEK_SET:
152         offset = av_clip(offset, 0, g->buffer_end - g->buffer_start);
153         g->buffer = g->buffer_start + offset;
154         break;
155     default:
156         return AVERROR(EINVAL);
157     }
158     return bytestream2_tell(g);
159 }
160
161 static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g,
162                                                             uint8_t *dst,
163                                                             unsigned int size)
164 {
165     int size2 = FFMIN(g->buffer_end - g->buffer, size);
166     memcpy(dst, g->buffer, size2);
167     g->buffer += size2;
168     return size2;
169 }
170
171 static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b, uint8_t *dst, unsigned int size)
172 {
173     memcpy(dst, *b, size);
174     (*b) += size;
175     return size;
176 }
177
178 static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
179 {
180     memcpy(*b, src, size);
181     (*b) += size;
182 }
183
184 #endif /* AVCODEC_BYTESTREAM_H */