From b77de4fb3b253c8ab9459853d092825dddd9af1b Mon Sep 17 00:00:00 2001
From: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Date: Mon, 3 Mar 2025 17:26:00 +0100
Subject: [PATCH 08/77] avcodec/mpegvideo: Don't initialize [yc]_dc_scale_table
by default
Only the H.263-based decoders as well as the encoders need it;
so move it to ff_h263_decode_init() as well as ff_mpv_encode_init().
Also for the latter make it only set these tables if none are
already set.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
---
libavcodec/h263dec.c | 5 ++++-
libavcodec/mpegvideo.c | 2 --
libavcodec/mpegvideo_enc.c | 6 +++++-
3 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index 2d806fc703..8434f6e7cf 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -41,8 +41,8 @@
#include "mpeg_er.h"
#include "mpeg4video.h"
#include "mpeg4videodec.h"
-#include "mpeg4videodefs.h"
#include "mpegvideo.h"
+#include "mpegvideodata.h"
#include "mpegvideodec.h"
#include "msmpeg4dec.h"
#include "thread.h"
@@ -102,6 +102,9 @@ av_cold int ff_h263_decode_init(AVCodecContext *avctx)
s->decode_mb = ff_h263_decode_mb;
s->low_delay = 1;
+ s->y_dc_scale_table =
+ s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
+
// dct_unquantize defaults for H.263;
// they might change on a per-frame basis for MPEG-4.
s->dct_unquantize_intra = s->dct_unquantize_h263_intra;
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 4b69b5b65c..9cd67151aa 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -482,8 +482,6 @@ int ff_update_duplicate_context(MpegEncContext *dst, const MpegEncContext *src)
*/
av_cold void ff_mpv_common_defaults(MpegEncContext *s)
{
- s->y_dc_scale_table =
- s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
s->chroma_qscale_table = ff_default_chroma_qscale_table;
s->progressive_frame = 1;
s->progressive_sequence = 1;
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index 5c2f73b2d1..7eb381af36 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -276,7 +276,6 @@ static av_cold void mpv_encode_init_static(void)
/**
* Set the given MpegEncContext to defaults for encoding.
- * the changed fields will not depend upon the prior state of the MpegEncContext.
*/
static av_cold void mpv_encode_defaults(MpegEncContext *s)
{
@@ -288,6 +287,11 @@ static av_cold void mpv_encode_defaults(MpegEncContext *s)
s->fcode_tab = default_fcode_tab + MAX_MV;
+ if (!s->y_dc_scale_table) {
+ s->y_dc_scale_table =
+ s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
+ }
+
s->input_picture_number = 0;
s->picture_in_gop_number = 0;
}
--
2.45.2