avfilter/mp_decimate: remove avcodec dependency

configure

@@ -2551,8 +2551,8 @@ ladspa_filter_extralibs='$ldl'
 mcdeint_filter_deps="avcodec gpl"
 movie_filter_deps="avcodec avformat"
 mp_filter_deps="gpl avcodec swscale inline_asm"
-mpdecimate_filter_deps="gpl avcodec"
-mpdecimate_filter_select="me_cmp pixblockdsp"
+mpdecimate_filter_deps="gpl"
+mpdecimate_filter_select="pixelutils"
 mptestsrc_filter_deps="gpl"
 negate_filter_deps="lut_filter"
 perspective_filter_deps="gpl"

libavfilter/vf_mpdecimate.c

@@ -26,9 +26,8 @@
 
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
+#include "libavutil/pixelutils.h"
 #include "libavutil/timestamp.h"
-#include "libavcodec/dsputil.h"
-#include "libavcodec/pixblockdsp.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "formats.h"
@@ -49,9 +48,7 @@ typedef struct {
 
     int hsub, vsub;                ///< chroma subsampling values
     AVFrame *ref;                  ///< reference picture
-    DSPContext dspctx;             ///< context providing optimized diff routines
-    PixblockDSPContext pdsp;
-    AVCodecContext *avctx;         ///< codec context required for the DSPContext
+    av_pixelutils_sad_fn sad;      ///< sum of absolute difference function
 } DecimateContext;
 
 #define OFFSET(x) offsetof(DecimateContext, x)
@@ -72,25 +69,21 @@ AVFILTER_DEFINE_CLASS(mpdecimate);
  * Return 1 if the two planes are different, 0 otherwise.
  */
 static int diff_planes(AVFilterContext *ctx,
-                       uint8_t *cur, uint8_t *ref, int linesize,
+                       uint8_t *cur, int cur_linesize,
+                       uint8_t *ref, int ref_linesize,
                        int w, int h)
 {
     DecimateContext *decimate = ctx->priv;
-    DSPContext *dspctx = &decimate->dspctx;
-    PixblockDSPContext *pdsp = &decimate->pdsp;
 
     int x, y;
     int d, c = 0;
     int t = (w/16)*(h/16)*decimate->frac;
-    int16_t block[8*8];
 
     /* compute difference for blocks of 8x8 bytes */
     for (y = 0; y < h-7; y += 4) {
         for (x = 8; x < w-7; x += 4) {
-            pdsp->diff_pixels(block,
-                                cur+x+y*linesize,
-                                ref+x+y*linesize, linesize);
-            d = dspctx->sum_abs_dctelem(block);
+            d = decimate->sad(cur + y*cur_linesize + x, cur_linesize,
+                              ref + y*ref_linesize + x, ref_linesize);
             if (d > decimate->hi)
                 return 1;
             if (d > decimate->lo) {
@@ -124,7 +117,8 @@ static int decimate_frame(AVFilterContext *ctx,
         int vsub = plane == 1 || plane == 2 ? decimate->vsub : 0;
         int hsub = plane == 1 || plane == 2 ? decimate->hsub : 0;
         if (diff_planes(ctx,
-                        cur->data[plane], ref->data[plane], ref->linesize[plane],
+                        cur->data[plane], cur->linesize[plane],
+                        ref->data[plane], ref->linesize[plane],
                         FF_CEIL_RSHIFT(ref->width,  hsub),
                         FF_CEIL_RSHIFT(ref->height, vsub)))
             return 0;
@@ -137,15 +131,13 @@ static av_cold int init(AVFilterContext *ctx)
 {
     DecimateContext *decimate = ctx->priv;
 
+    decimate->sad = av_pixelutils_get_sad_fn(3, 3, 0, decimate); // 8x8, not aligned on blocksize
+    if (!decimate->sad)
+        return AVERROR(EINVAL);
+
     av_log(ctx, AV_LOG_VERBOSE, "max_drop_count:%d hi:%d lo:%d frac:%f\n",
            decimate->max_drop_count, decimate->hi, decimate->lo, decimate->frac);
 
-    decimate->avctx = avcodec_alloc_context3(NULL);
-    if (!decimate->avctx)
-        return AVERROR(ENOMEM);
-    avpriv_dsputil_init(&decimate->dspctx, decimate->avctx);
-    ff_pixblockdsp_init(&decimate->pdsp, decimate->avctx);
-
     return 0;
 }
 
@@ -153,10 +145,6 @@ static av_cold void uninit(AVFilterContext *ctx)
 {
     DecimateContext *decimate = ctx->priv;
     av_frame_free(&decimate->ref);
-    if (decimate->avctx) {
-        avcodec_close(decimate->avctx);
-        av_freep(&decimate->avctx);
-    }
 }
 
 static int query_formats(AVFilterContext *ctx)