added work buffer for denoiser

The denoiser was writing to LAST_FRAME buffer.   If LAST_FRAME isn't being
updated,  the reference frame buffers were out of sync between the encoder and the
denoised raw buffers. This patch resolves the discrepancy by always writing to a work
buffer (INTRA_FRAME) and then copying from that buffer to any buffers that needs to
be updated.

Change-Id: I6dd855b9749978b542bc3d515914d5f16faf25df

vp8/encoder/denoising.c

diff --git a/vp8/encoder/denoising.c b/vp8/encoder/denoising.c
index c0dd7c1..f3faa22 100644
--- a/vp8/encoder/denoising.c
+++ b/vp8/encoder/denoising.c
@@ -140,8 +140,7 @@
     int i;
     assert(denoiser);
 
-    /* don't need one for intra start at 1 */
-    for (i = 1; i < MAX_REF_FRAMES; i++)
+    for (i = 0; i < MAX_REF_FRAMES; i++)
     {
         denoiser->yv12_running_avg[i].flags = 0;
 
@@ -175,8 +174,7 @@
     int i;
     assert(denoiser);
 
-    /* we don't have one for intra ref frame */
-    for (i = 1; i < MAX_REF_FRAMES ; i++)
+    for (i = 0; i < MAX_REF_FRAMES ; i++)
     {
         vp8_yv12_de_alloc_frame_buffer(&denoiser->yv12_running_avg[i]);
     }
@@ -291,7 +289,7 @@
     {
         /* Filter. */
         decision = vp8_denoiser_filter(&denoiser->yv12_mc_running_avg,
-                                       &denoiser->yv12_running_avg[LAST_FRAME],
+                                       &denoiser->yv12_running_avg[INTRA_FRAME],
                                        x,
                                        motion_magnitude2,
                                        recon_yoffset, recon_uvoffset);
@@ -303,7 +301,7 @@
          */
         vp8_copy_mem16x16(
                 x->thismb, 16,
-                denoiser->yv12_running_avg[LAST_FRAME].y_buffer + recon_yoffset,
-                denoiser->yv12_running_avg[LAST_FRAME].y_stride);
+                denoiser->yv12_running_avg[INTRA_FRAME].y_buffer + recon_yoffset,
+                denoiser->yv12_running_avg[INTRA_FRAME].y_stride);
     }
 }

vp8/encoder/onyx_if.c

diff --git a/vp8/encoder/onyx_if.c b/vp8/encoder/onyx_if.c
index f0e0da0..3847c1e 100644
--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -3177,8 +3177,6 @@
 #if CONFIG_TEMPORAL_DENOISING
     if (cpi->oxcf.noise_sensitivity)
     {
-
-
         /* we shouldn't have to keep multiple copies as we know in advance which
          * buffer we should start - for now to get something up and running
          * I've chosen to copy the buffers
@@ -3195,26 +3193,32 @@
 
             for (i = 2; i < MAX_REF_FRAMES - 1; i++)
                 vp8_yv12_copy_frame(
-                        cpi->Source,
+                        &cpi->denoiser.yv12_running_avg[LAST_FRAME],
                         &cpi->denoiser.yv12_running_avg[i]);
         }
         else /* For non key frames */
         {
             vp8_yv12_extend_frame_borders(
-                    &cpi->denoiser.yv12_running_avg[LAST_FRAME]);
+                    &cpi->denoiser.yv12_running_avg[INTRA_FRAME]);
 
             if (cm->refresh_alt_ref_frame || cm->copy_buffer_to_arf)
             {
                 vp8_yv12_copy_frame(
-                        &cpi->denoiser.yv12_running_avg[LAST_FRAME],
+                        &cpi->denoiser.yv12_running_avg[INTRA_FRAME],
                         &cpi->denoiser.yv12_running_avg[ALTREF_FRAME]);
             }
             if (cm->refresh_golden_frame || cm->copy_buffer_to_gf)
             {
                 vp8_yv12_copy_frame(
-                        &cpi->denoiser.yv12_running_avg[LAST_FRAME],
+                        &cpi->denoiser.yv12_running_avg[INTRA_FRAME],
                         &cpi->denoiser.yv12_running_avg[GOLDEN_FRAME]);
             }
+            if(cm->refresh_last_frame)
+            {
+                vp8_yv12_copy_frame(
+                        &cpi->denoiser.yv12_running_avg[INTRA_FRAME],
+                        &cpi->denoiser.yv12_running_avg[LAST_FRAME]);
+            }
         }
 
     }