Split MPEG-1/2 decoder code off from MPEG-1/2 common code
[libav.git] / libavcodec / mpeg12.h
1 /*
2 * MPEG1/2 common code
3 * Copyright (c) 2007 Aurelien Jacobs <aurel@gnuage.org>
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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_MPEG12_H
23 #define AVCODEC_MPEG12_H
24
25 #include "mpegvideo.h"
26
27 #define DC_VLC_BITS 9
28 #define MV_VLC_BITS 9
29 #define TEX_VLC_BITS 9
30
31 #define MBINCR_VLC_BITS 9
32 #define MB_PAT_VLC_BITS 9
33 #define MB_PTYPE_VLC_BITS 6
34 #define MB_BTYPE_VLC_BITS 6
35
36 extern VLC ff_dc_lum_vlc;
37 extern VLC ff_dc_chroma_vlc;
38 extern VLC ff_mbincr_vlc;
39 extern VLC ff_mb_ptype_vlc;
40 extern VLC ff_mb_btype_vlc;
41 extern VLC ff_mb_pat_vlc;
42 extern VLC ff_mv_vlc;
43
44 typedef struct Mpeg1Context {
45 MpegEncContext mpeg_enc_ctx;
46 int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
47 int repeat_field; /* true if we must repeat the field */
48 AVPanScan pan_scan; /**< some temporary storage for the panscan */
49 int slice_count;
50 int swap_uv;//indicate VCR2
51 int save_aspect_info;
52 int save_width, save_height, save_progressive_seq;
53 AVRational frame_rate_ext; ///< MPEG-2 specific framerate modificator
54 int sync; ///< Did we reach a sync point like a GOP/SEQ/KEYFrame?
55 int closed_gop; ///< GOP is closed
56 int extradata_decoded;
57 } Mpeg1Context;
58
59 extern uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
60
61 void ff_mpeg12_common_init(MpegEncContext *s);
62 void ff_mpeg12_init_vlcs(void);
63
64 static inline int decode_dc(GetBitContext *gb, int component)
65 {
66 int code, diff;
67
68 if (component == 0) {
69 code = get_vlc2(gb, ff_dc_lum_vlc.table, DC_VLC_BITS, 2);
70 } else {
71 code = get_vlc2(gb, ff_dc_chroma_vlc.table, DC_VLC_BITS, 2);
72 }
73 if (code < 0){
74 av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
75 return 0xffff;
76 }
77 if (code == 0) {
78 diff = 0;
79 } else {
80 diff = get_xbits(gb, code);
81 }
82 return diff;
83 }
84
85 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n);
86 void ff_mpeg1_clean_buffers(MpegEncContext *s);
87 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s);
88
89 #endif /* AVCODEC_MPEG12_H */