1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-28 20:53:54 +02:00
FFmpeg/libavcodec/dcahuff.h

76 lines
2.4 KiB
C
Raw Normal View History

/*
* DCA compatible decoder - huffman tables
* Copyright (C) 2004 Gildas Bazin
* Copyright (C) 2007 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_DCAHUFF_H
#define AVCODEC_DCAHUFF_H
#include <stdint.h>
#include "libavutil/attributes.h"
#include "vlc.h"
#define DCA_CODE_BOOKS 10
#define DCA_BITALLOC_12_COUNT 5
#define DCA_NUM_BITALLOC_CODES (1 * 3 + \
3 * (5 + 7 + 9 + 13) \
+ 7 * (17 + 25 + 33 + 65 + 129))
extern VLC ff_dca_vlc_bit_allocation[5];
#define DCA_TMODE_VLC_BITS 3
extern VLC ff_dca_vlc_transition_mode[4];
#define DCA_SCALES_VLC_BITS 9
extern VLC ff_dca_vlc_scale_factor[5];
extern VLC ff_dca_vlc_quant_index[DCA_CODE_BOOKS][7];
#define DCA_TNL_GRP_VLC_BITS 9
extern VLC ff_dca_vlc_tnl_grp[5];
#define DCA_TNL_SCF_VLC_BITS 9
extern VLC ff_dca_vlc_tnl_scf;
#define DCA_DAMP_VLC_BITS 6
extern VLC ff_dca_vlc_damp;
#define DCA_DPH_VLC_BITS 6
extern VLC ff_dca_vlc_dph;
#define DCA_FST_RSD_VLC_BITS 9
extern VLC ff_dca_vlc_fst_rsd_amp;
#define DCA_RSD_APPRX_VLC_BITS 5
extern VLC ff_dca_vlc_rsd_apprx;
#define DCA_RSD_AMP_VLC_BITS 9
extern VLC ff_dca_vlc_rsd_amp;
#define DCA_AVG_G3_VLC_BITS 9
extern VLC ff_dca_vlc_avg_g3;
#define DCA_ST_GRID_VLC_BITS 9
extern VLC ff_dca_vlc_st_grid;
#define DCA_GRID_VLC_BITS 9
extern VLC ff_dca_vlc_grid_2;
extern VLC ff_dca_vlc_grid_3;
#define DCA_RSD_VLC_BITS 6
extern VLC ff_dca_vlc_rsd;
extern const int8_t ff_dca_bitalloc_offsets[DCA_CODE_BOOKS];
extern const uint8_t ff_dca_bitalloc_sizes[DCA_CODE_BOOKS];
avcodec/dcahuff: Combine tables, use ff_init_vlc_from_lengths() Up until now, initializing the dca VLC tables uses ff_init_vlc_sparse() with length tables of type uint8_t and code tables of type uint16_t (except for the LBR tables, which uses length and symbols of type uint8_t; these tables are interleaved). In case of the quant index codebooks these arrays were accessed via tables of pointers to the individual tables. This commit changes this: First, we switch to ff_init_vlc_from_lengths() to replace the uint16_t code tables by uint8_t symbol tables (this necessitates ordering the tables from left-to-right in the tree first). These symbol tables are interleaved with the length tables. Furthermore, these tables are combined in order to remove the table of pointers to individual tables, thereby avoiding relocations (for x64 elf systems this amounts to 96*24B = 2304B saved in .rela.dyn) and saving 1280B from .data.rel.ro (for 64bit systems). Meanwhile the savings in .rodata amount to 2709 + 2 * 334 = 3377B. Due to padding the actual savings are higher: The ELF x64 ABI requires objects >= 16B to be padded to 16B and lots of the tables have 2^n + 1 elements of these were from replacing uint16_t codes with uint8_t symbols; the rest was due to the fact that combining the tables eliminated padding (the ELF x64 ABI requires objects >= 16B to be padded to 16B and lots of the tables have 2^n + 1 elements)). Taking this into account gives savings of 4548B. (GCC by default uses an even higher alignment (controlled by -malign-data); for it the savings are 5748B.) These changes also necessitated to modify the init code for the encoder tables. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-06 02:12:14 +02:00
extern const uint8_t ff_dca_vlc_src_tables[][2];
av_cold void ff_dca_init_vlcs(void);
#endif /* AVCODEC_DCAHUFF_H */