avcodec/mpegpicture: Avoid MotionEstContext in ff_mpeg_framesize_alloc()

Only set the ScratchpadContext and let the users that need it
(i.e. encoders) set the MotionEstContext stuff themselves.
Also add an explicit pointer to ScratchpadContext to point
to the allocated buffer so that none of the other scratchpad
pointers is singled out as being used for the allocations.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

6 files changed, 24 insertions, 30 deletions

diff --git a/libavcodec/mpegpicture.c b/libavcodec/mpegpicture.c
index 43d35934c8..cde060aa1f 100644
--- a/libavcodec/mpegpicture.c
+++ b/libavcodec/mpegpicture.c
@@ -25,7 +25,6 @@
 #include "libavutil/imgutils.h"
 
 #include "avcodec.h"
-#include "motion_est.h"
 #include "mpegpicture.h"
 #include "refstruct.h"
 
@@ -136,8 +135,8 @@ void ff_mpv_workpic_from_pic(MPVWorkPicture *wpic, MPVPicture *pic)
     set_workpic_from_pic(wpic, pic);
 }
 
-int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
-                            ScratchpadContext *sc, int linesize)
+int ff_mpv_framesize_alloc(AVCodecContext *avctx,
+                           ScratchpadContext *sc, int linesize)
 {
 #   define EMU_EDGE_HEIGHT (4 * 70)
     int linesizeabs = FFABS(linesize);
@@ -158,7 +157,7 @@ int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
         return AVERROR(ENOMEM);
 
     av_freep(&sc->edge_emu_buffer);
-    av_freep(&me->scratchpad);
+    av_freep(&sc->scratchpad_buf);
 
     // edge emu needs blocksize + filter length - 1
     // (= 17x17 for  halfpel / 21x21 for H.264)
@@ -167,16 +166,14 @@ int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
     // linesize * interlaced * MBsize
     // we also use this buffer for encoding in encode_mb_internal() needig an additional 32 lines
     if (!FF_ALLOCZ_TYPED_ARRAY(sc->edge_emu_buffer, alloc_size * EMU_EDGE_HEIGHT) ||
-        !FF_ALLOCZ_TYPED_ARRAY(me->scratchpad,      alloc_size * 4 * 16 * 2)) {
+        !FF_ALLOCZ_TYPED_ARRAY(sc->scratchpad_buf,  alloc_size * 4 * 16 * 2)) {
         sc->linesize = 0;
         av_freep(&sc->edge_emu_buffer);
         return AVERROR(ENOMEM);
     }
     sc->linesize = linesizeabs;
 
-    me->temp            = me->scratchpad;
-    sc->b_scratchpad    = me->scratchpad;
-    sc->obmc_scratchpad = me->scratchpad + 16;
+    sc->obmc_scratchpad = sc->scratchpad_buf + 16;
 
     return 0;
 }
@@ -238,14 +235,13 @@ static int alloc_picture_tables(BufferPoolContext *pools, MPVPicture *pic,
 }
 
 int ff_mpv_alloc_pic_accessories(AVCodecContext *avctx, MPVWorkPicture *wpic,
-                                 MotionEstContext *me, ScratchpadContext *sc,
+                                 ScratchpadContext *sc,
                                  BufferPoolContext *pools, int mb_height)
 {
     MPVPicture *pic = wpic->ptr;
     int ret;
 
-    ret = ff_mpeg_framesize_alloc(avctx, me, sc,
-                                  pic->f->linesize[0]);
+    ret = ff_mpv_framesize_alloc(avctx, sc, pic->f->linesize[0]);
     if (ret < 0)
         goto fail;
 
diff --git a/libavcodec/mpegpicture.h b/libavcodec/mpegpicture.h
index ddb3ac5a2b..86504fe8ca 100644
--- a/libavcodec/mpegpicture.h
+++ b/libavcodec/mpegpicture.h
@@ -25,7 +25,6 @@
 #include <stdint.h>
 
 #include "avcodec.h"
-#include "motion_est.h"
 #include "threadprogress.h"
 
 #define MPV_MAX_PLANES 3
@@ -35,6 +34,7 @@ typedef struct ScratchpadContext {
     uint8_t *edge_emu_buffer;     ///< temporary buffer for if MVs point to out-of-frame data
     uint8_t *obmc_scratchpad;
     union {
+        uint8_t *scratchpad_buf;  ///< the other *_scratchpad point into this buffer
         uint8_t *b_scratchpad;    ///< scratchpad used for writing into write only buffers
         uint8_t *rd_scratchpad;   ///< scratchpad for rate distortion mb decision
     };
@@ -121,7 +121,7 @@ struct FFRefStructPool *ff_mpv_alloc_pic_pool(int init_progress);
  * and set the MPVWorkPicture's fields.
  */
 int ff_mpv_alloc_pic_accessories(AVCodecContext *avctx, MPVWorkPicture *pic,
-                                 MotionEstContext *me, ScratchpadContext *sc,
+                                 ScratchpadContext *sc,
                                  BufferPoolContext *pools, int mb_height);
 
 /**
@@ -133,8 +133,8 @@ int ff_mpv_alloc_pic_accessories(AVCodecContext *avctx, MPVWorkPicture *pic,
 int ff_mpv_pic_check_linesize(void *logctx, const struct AVFrame *f,
                               ptrdiff_t *linesizep, ptrdiff_t *uvlinesizep);
 
-int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
-                            ScratchpadContext *sc, int linesize);
+int ff_mpv_framesize_alloc(AVCodecContext *avctx,
+                           ScratchpadContext *sc, int linesize);
 
 void ff_mpv_unref_picture(MPVWorkPicture *pic);
 void ff_mpv_workpic_from_pic(MPVWorkPicture *wpic, MPVPicture *pic);
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 36947c6e31..89d19a743a 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -438,9 +438,8 @@ static void free_duplicate_context(MpegEncContext *s)
         return;
 
     av_freep(&s->sc.edge_emu_buffer);
-    av_freep(&s->me.scratchpad);
-    s->me.temp =
-    s->sc.b_scratchpad =
+    av_freep(&s->sc.scratchpad_buf);
+    s->me.temp = s->me.scratchpad =
     s->sc.obmc_scratchpad = NULL;
     s->sc.linesize = 0;
 
@@ -465,8 +464,6 @@ static void backup_duplicate_context(MpegEncContext *bak, MpegEncContext *src)
 {
 #define COPY(a) bak->a = src->a
     COPY(sc);
-    COPY(me.scratchpad);
-    COPY(me.temp);
     COPY(me.map);
     COPY(me.score_map);
     COPY(blocks);
@@ -500,8 +497,7 @@ int ff_update_duplicate_context(MpegEncContext *dst, const MpegEncContext *src)
         // exchange uv
         FFSWAP(void *, dst->pblocks[4], dst->pblocks[5]);
     }
-    ret = ff_mpeg_framesize_alloc(dst->avctx, &dst->me,
-                                  &dst->sc, dst->linesize);
+    ret = ff_mpv_framesize_alloc(dst->avctx, &dst->sc, dst->linesize);
     if (ret < 0) {
         av_log(dst->avctx, AV_LOG_ERROR, "failed to allocate context "
                "scratch buffers.\n");
diff --git a/libavcodec/mpegvideo_dec.c b/libavcodec/mpegvideo_dec.c
index b7f72ad460..9d2b7671e3 100644
--- a/libavcodec/mpegvideo_dec.c
+++ b/libavcodec/mpegvideo_dec.c
@@ -155,8 +155,7 @@ int ff_mpeg_update_thread_context(AVCodecContext *dst,
     }
 
     // linesize-dependent scratch buffer allocation
-    ret = ff_mpeg_framesize_alloc(s->avctx, &s->me,
-                                  &s->sc, s1->linesize);
+    ret = ff_mpv_framesize_alloc(s->avctx, &s->sc, s1->linesize);
     if (ret < 0) {
         av_log(s->avctx, AV_LOG_ERROR, "Failed to allocate context "
                "scratch buffers.\n");
@@ -264,7 +263,7 @@ static int alloc_picture(MpegEncContext *s, MPVWorkPicture *dst, int reference)
     av_assert1(s->mb_height == s->buffer_pools.alloc_mb_height ||
                FFALIGN(s->mb_height, 2) == s->buffer_pools.alloc_mb_height);
     av_assert1(s->mb_stride == s->buffer_pools.alloc_mb_stride);
-    ret = ff_mpv_alloc_pic_accessories(s->avctx, dst, &s->me, &s->sc,
+    ret = ff_mpv_alloc_pic_accessories(s->avctx, dst, &s->sc,
                                        &s->buffer_pools, s->mb_height);
     if (ret < 0)
         goto fail;
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index d131be964b..eaaf366624 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -1663,12 +1663,13 @@ static int select_input_picture(MpegEncContext *s)
         av_assert1(s->mb_width  == s->buffer_pools.alloc_mb_width);
         av_assert1(s->mb_height == s->buffer_pools.alloc_mb_height);
         av_assert1(s->mb_stride == s->buffer_pools.alloc_mb_stride);
-        ret = ff_mpv_alloc_pic_accessories(s->avctx, &s->cur_pic, &s->me,
+        ret = ff_mpv_alloc_pic_accessories(s->avctx, &s->cur_pic,
                                            &s->sc, &s->buffer_pools, s->mb_height);
         if (ret < 0) {
             ff_mpv_unref_picture(&s->cur_pic);
             return ret;
         }
+        s->me.temp = s->me.scratchpad = s->sc.scratchpad_buf;
         s->picture_number = s->cur_pic.ptr->display_picture_number;
 
     }
@@ -3616,9 +3617,11 @@ static int encode_picture(MpegEncContext *s)
 
     s->mb_intra=0; //for the rate distortion & bit compare functions
     for(i=1; i<context_count; i++){
-        ret = ff_update_duplicate_context(s->thread_context[i], s);
+        MpegEncContext *const slice = s->thread_context[i];
+        ret = ff_update_duplicate_context(slice, s);
         if (ret < 0)
             return ret;
+        slice->me.temp = slice->me.scratchpad = slice->sc.scratchpad_buf;
     }
 
     /* Estimate motion for every MB */
diff --git a/libavcodec/svq1enc.c b/libavcodec/svq1enc.c
index 9c9be8c6b3..35413b8afd 100644
--- a/libavcodec/svq1enc.c
+++ b/libavcodec/svq1enc.c
@@ -543,15 +543,15 @@ static av_cold int svq1_encode_end(AVCodecContext *avctx)
                s->rd_total / (double)(avctx->width * avctx->height *
                                       avctx->frame_num));
 
-    s->m.mb_type = NULL;
-    ff_mpv_common_end(&s->m);
-
     av_freep(&s->m.me.scratchpad);
     av_freep(&s->m.me.map);
     av_freep(&s->mb_type);
     av_freep(&s->dummy);
     av_freep(&s->scratchbuf);
 
+    s->m.mb_type = NULL;
+    ff_mpv_common_end(&s->m);
+
     for (i = 0; i < 3; i++) {
         av_freep(&s->motion_val8[i]);
         av_freep(&s->motion_val16[i]);