virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
Code Issues Releases Activity
905c4dc2b0
FFmpeg/libavcodec/x86/rv34dsp.asm

56 lines
1.7 KiB
NASM
Raw Normal View History

rv34: DC-only inverse transform When decoding coefficients, detect whether the block is DC-only, and take advantage of this knowledge to perform DC-only inverse transform. This is achieved by: - first, changing the 108x4 element modulo_three_table into a 108 element table (kind of base4), and accessing each value using mask and shifts. - then, checking low bits for 0 (as they represent the presence of higher frequency coefficients) Also provide x86 SIMD code for the DC-only inverse transform. Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>
2012-01-01 20:33:22 +03:00
;******************************************************************************
;* MMX/SSE2-optimized functions for the RV30 and RV40 decoders
;* Copyright (C) 2012 Christophe Gisquet <christophe.gisquet@gmail.com>
;*
;* This file is part of Libav.
;*
;* Libav 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.
;*
;* Libav 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 Libav; if not, write to the Free Software
;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;******************************************************************************
%include "x86inc.asm"
%include "x86util.asm"
SECTION .text
%macro IDCT_DC_NOROUND 1
imul %1, 13*13*3
sar %1, 11
%endmacro
%macro IDCT_DC_ROUND 1
imul %1, 13*13
add %1, 0x200
sar %1, 10
%endmacro
%macro rv34_idct_dequant4x4_dc 1
cglobal rv34_idct_dequant4x4_%1_mmx2, 1, 2, 0
movsx r1, word [r0]
IDCT_DC r1
Use correct register size, fixes compilation with NASM. Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
2012-01-14 19:42:57 +03:00
movd mm0, r1d
rv34: DC-only inverse transform When decoding coefficients, detect whether the block is DC-only, and take advantage of this knowledge to perform DC-only inverse transform. This is achieved by: - first, changing the 108x4 element modulo_three_table into a 108 element table (kind of base4), and accessing each value using mask and shifts. - then, checking low bits for 0 (as they represent the presence of higher frequency coefficients) Also provide x86 SIMD code for the DC-only inverse transform. Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>
2012-01-01 20:33:22 +03:00
pshufw mm0, mm0, 0
movq [r0+ 0], mm0
movq [r0+16], mm0
movq [r0+32], mm0
movq [r0+48], mm0
REP_RET
%endmacro
INIT_MMX
%define IDCT_DC IDCT_DC_ROUND
rv34_idct_dequant4x4_dc dc
%define IDCT_DC IDCT_DC_NOROUND
rv34_idct_dequant4x4_dc dc_noround
Reference in New Issue Copy Permalink