• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 /**
20  * @file
21  * H.264 common definitions
22  */
23 
24 #ifndef AVCODEC_H264_H
25 #define AVCODEC_H264_H
26 
27 #define QP_MAX_NUM (51 + 6*6)           // The maximum supported qp
28 
29 /*
30  * Table 7-1 – NAL unit type codes, syntax element categories, and NAL unit type classes in
31  * T-REC-H.264-201704
32  */
33 enum {
34     H264_NAL_UNSPECIFIED     = 0,
35     H264_NAL_SLICE           = 1,
36     H264_NAL_DPA             = 2,
37     H264_NAL_DPB             = 3,
38     H264_NAL_DPC             = 4,
39     H264_NAL_IDR_SLICE       = 5,
40     H264_NAL_SEI             = 6,
41     H264_NAL_SPS             = 7,
42     H264_NAL_PPS             = 8,
43     H264_NAL_AUD             = 9,
44     H264_NAL_END_SEQUENCE    = 10,
45     H264_NAL_END_STREAM      = 11,
46     H264_NAL_FILLER_DATA     = 12,
47     H264_NAL_SPS_EXT         = 13,
48     H264_NAL_PREFIX          = 14,
49     H264_NAL_SUB_SPS         = 15,
50     H264_NAL_DPS             = 16,
51     H264_NAL_RESERVED17      = 17,
52     H264_NAL_RESERVED18      = 18,
53     H264_NAL_AUXILIARY_SLICE = 19,
54     H264_NAL_EXTEN_SLICE     = 20,
55     H264_NAL_DEPTH_EXTEN_SLICE = 21,
56     H264_NAL_RESERVED22      = 22,
57     H264_NAL_RESERVED23      = 23,
58     H264_NAL_UNSPECIFIED24   = 24,
59     H264_NAL_UNSPECIFIED25   = 25,
60     H264_NAL_UNSPECIFIED26   = 26,
61     H264_NAL_UNSPECIFIED27   = 27,
62     H264_NAL_UNSPECIFIED28   = 28,
63     H264_NAL_UNSPECIFIED29   = 29,
64     H264_NAL_UNSPECIFIED30   = 30,
65     H264_NAL_UNSPECIFIED31   = 31,
66 };
67 
68 
69 enum {
70     // 7.4.2.1.1: seq_parameter_set_id is in [0, 31].
71     H264_MAX_SPS_COUNT = 32,
72     // 7.4.2.2: pic_parameter_set_id is in [0, 255].
73     H264_MAX_PPS_COUNT = 256,
74 
75     // A.3: MaxDpbFrames is bounded above by 16.
76     H264_MAX_DPB_FRAMES = 16,
77     // 7.4.2.1.1: max_num_ref_frames is in [0, MaxDpbFrames], and
78     // each reference frame can have two fields.
79     H264_MAX_REFS       = 2 * H264_MAX_DPB_FRAMES,
80 
81     // 7.4.3.1: modification_of_pic_nums_idc is not equal to 3 at most
82     // num_ref_idx_lN_active_minus1 + 1 times (that is, once for each
83     // possible reference), then equal to 3 once.
84     H264_MAX_RPLM_COUNT = H264_MAX_REFS + 1,
85 
86     // 7.4.3.3: in the worst case, we begin with a full short-term
87     // reference picture list.  Each picture in turn is moved to the
88     // long-term list (type 3) and then discarded from there (type 2).
89     // Then, we set the length of the long-term list (type 4), mark
90     // the current picture as long-term (type 6) and terminate the
91     // process (type 0).
92     H264_MAX_MMCO_COUNT = H264_MAX_REFS * 2 + 3,
93 
94     // A.2.1, A.2.3: profiles supporting FMO constrain
95     // num_slice_groups_minus1 to be in [0, 7].
96     H264_MAX_SLICE_GROUPS = 8,
97 
98     // E.2.2: cpb_cnt_minus1 is in [0, 31].
99     H264_MAX_CPB_CNT = 32,
100 
101     // A.3: in table A-1 the highest level allows a MaxFS of 139264.
102     H264_MAX_MB_PIC_SIZE = 139264,
103     // A.3.1, A.3.2: PicWidthInMbs and PicHeightInMbs are constrained
104     // to be not greater than sqrt(MaxFS * 8).  Hence height/width are
105     // bounded above by sqrt(139264 * 8) = 1055.5 macroblocks.
106     H264_MAX_MB_WIDTH    = 1055,
107     H264_MAX_MB_HEIGHT   = 1055,
108     H264_MAX_WIDTH       = H264_MAX_MB_WIDTH  * 16,
109     H264_MAX_HEIGHT      = H264_MAX_MB_HEIGHT * 16,
110 };
111 
112 
113 #endif /* AVCODEC_H264_H */
114