[FFmpeg-devel] [PATCH 2/4] lavc/mpegvideo: use H263DSP dequant function

Rémi Denis-Courmont remi at remlab.net
Wed Jun 12 07:47:21 EEST 2024


---
 configure              |  4 ++--
 libavcodec/mpegvideo.c | 46 +++++++++++-------------------------------
 2 files changed, 14 insertions(+), 36 deletions(-)

diff --git a/configure b/configure
index 6baa9b0646..eb9d1b1f5d 100755
--- a/configure
+++ b/configure
@@ -2957,8 +2957,8 @@ ftr_decoder_select="adts_header"
 g2m_decoder_deps="zlib"
 g2m_decoder_select="blockdsp idctdsp jpegtables"
 g729_decoder_select="audiodsp"
-h261_decoder_select="mpegvideodec"
-h261_encoder_select="mpegvideoenc"
+h261_decoder_select="h263dsp mpegvideodec"
+h261_encoder_select="h263dsp mpegvideoenc"
 h263_decoder_select="h263_parser h263dsp mpegvideodec qpeldsp"
 h263_encoder_select="h263dsp mpegvideoenc"
 h263i_decoder_select="h263_decoder"
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 7af823b8bd..b35fd37083 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -201,13 +201,11 @@ static void dct_unquantize_mpeg2_inter_c(MpegEncContext *s,
 static void dct_unquantize_h263_intra_c(MpegEncContext *s,
                                   int16_t *block, int n, int qscale)
 {
-    int i, level, qmul, qadd;
-    int nCoeffs;
+    int qmul = qscale << 1;
+    int qadd, nCoeffs;
 
     av_assert2(s->block_last_index[n]>=0 || s->h263_aic);
 
-    qmul = qscale << 1;
-
     if (!s->h263_aic) {
         block[0] *= n < 4 ? s->y_dc_scale : s->c_dc_scale;
         qadd = (qscale - 1) | 1;
@@ -215,47 +213,24 @@ static void dct_unquantize_h263_intra_c(MpegEncContext *s,
         qadd = 0;
     }
     if(s->ac_pred)
-        nCoeffs=63;
+        nCoeffs = 64;
     else
-        nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ];
+        nCoeffs = s->intra_scantable.raster_end[s->block_last_index[n]] + 1;
 
-    for(i=1; i<=nCoeffs; i++) {
-        level = block[i];
-        if (level) {
-            if (level < 0) {
-                level = level * qmul - qadd;
-            } else {
-                level = level * qmul + qadd;
-            }
-            block[i] = level;
-        }
-    }
+    s->h263dsp.h263_dct_unquantize_intra(block, nCoeffs, qmul, qadd);
 }
 
 static void dct_unquantize_h263_inter_c(MpegEncContext *s,
                                   int16_t *block, int n, int qscale)
 {
-    int i, level, qmul, qadd;
+    int qmul = qscale << 1;
+    int qadd = (qscale - 1) | 1;
     int nCoeffs;
 
     av_assert2(s->block_last_index[n]>=0);
 
-    qadd = (qscale - 1) | 1;
-    qmul = qscale << 1;
-
-    nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
-
-    for(i=0; i<=nCoeffs; i++) {
-        level = block[i];
-        if (level) {
-            if (level < 0) {
-                level = level * qmul - qadd;
-            } else {
-                level = level * qmul + qadd;
-            }
-            block[i] = level;
-        }
-    }
+    nCoeffs = s->inter_scantable.raster_end[s->block_last_index[n]] + 1;
+    s->h263dsp.h263_dct_unquantize_inter(block, nCoeffs, qmul, qadd);
 }
 
 
@@ -275,6 +250,9 @@ static void gray8(uint8_t *dst, const uint8_t *src, ptrdiff_t linesize, int h)
 static av_cold int dct_init(MpegEncContext *s)
 {
     ff_blockdsp_init(&s->bdsp);
+#if CONFIG_H263DSP
+    ff_h263dsp_init(&s->h263dsp);
+#endif
     ff_hpeldsp_init(&s->hdsp, s->avctx->flags);
     ff_videodsp_init(&s->vdsp, s->avctx->bits_per_raw_sample);
 
-- 
2.45.1



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