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e7a629049f
Forgotten in70a7df049c. Using the wrong scantable matters for codecs for which both scantables can differ, namely the MPEG-4 decoder and the WMV1/2 codecs. For WMV1 it can lead to wrong output in case the IDCT permutation is FF_IDCT_PERM_PARTTRANS, because in this case the entries of of the intra scantable's raster end are not always <= the corresponding entries of the inter scantable's raster end when the former is initialized via ff_wmv1_scantable[1] and the latter via ff_wmv1_scantable[0]. FF_IDCT_PERM_PARTTRANS is used iff the Neon IDCT is used (for both arm and aarch64).* Said IDCT is not used during FATE, so that this issue went unnoticed. WMV2 uses the same scantables, but uses a custom IDCT which always uses FF_IDCT_PERM_NONE for which the inter_scantable, so that the output is always correct for it. The scantable for MPEG-4 can change mid-stream (for the decoder), but sincec41818dc5donly the intra scantable is updated, so that both scantables can get out of sync. In such a case the unquantize intra functions could unquantize an incorrect number of coefficients. Using raster_end of the wrong scantable can also lead to an unnecessarily large amount of coefficients unquantized. *: FF_IDCT_PERM_SIMPLE and FF_IDCT_PERM_TRANSPOSE would also not work, but they are not used at all by arm and aarch64. Reviewed-by: Martin Storsjö <martin@martin.st> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
63 lines
2.3 KiB
C
63 lines
2.3 KiB
C
/*
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* Copyright (c) 2002 Michael Niedermayer
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <assert.h>
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#include "libavutil/attributes.h"
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#include "libavutil/arm/cpu.h"
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#include "libavcodec/avcodec.h"
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#include "libavcodec/mpegvideo.h"
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#include "libavcodec/mpegvideo_unquantize.h"
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#include "mpegvideo_arm.h"
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#include "asm-offsets.h"
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#if HAVE_NEON
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#define CHECK_OFFSET(s, m, o) \
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static_assert(offsetof(s, m) == o, \
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"Hardcoded ASM offset of " #s " field " #o " needs to be updated.");
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CHECK_OFFSET(MpegEncContext, y_dc_scale, Y_DC_SCALE);
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CHECK_OFFSET(MpegEncContext, c_dc_scale, C_DC_SCALE);
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CHECK_OFFSET(MpegEncContext, ac_pred, AC_PRED);
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CHECK_OFFSET(MpegEncContext, block_last_index, BLOCK_LAST_INDEX);
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CHECK_OFFSET(MpegEncContext, inter_scantable.raster_end,
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INTER_SCANTAB_RASTER_END);
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CHECK_OFFSET(MpegEncContext, intra_scantable.raster_end,
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INTRA_SCANTAB_RASTER_END);
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CHECK_OFFSET(MpegEncContext, h263_aic, H263_AIC);
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#endif
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void ff_dct_unquantize_h263_inter_neon(const MPVContext *s, int16_t *block,
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int n, int qscale);
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void ff_dct_unquantize_h263_intra_neon(const MPVContext *s, int16_t *block,
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int n, int qscale);
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av_cold void ff_mpv_unquantize_init_arm(MPVUnquantDSPContext *s, int bitexact)
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{
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int cpu_flags = av_get_cpu_flags();
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if (have_armv5te(cpu_flags))
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ff_mpv_unquantize_init_armv5te(s);
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if (have_neon(cpu_flags)) {
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s->dct_unquantize_h263_intra = ff_dct_unquantize_h263_intra_neon;
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s->dct_unquantize_h263_inter = ff_dct_unquantize_h263_inter_neon;
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}
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}
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