Fix sporadic vertical stripes with planar fast image thresholding (pkmraw)

In the landscape code, only the data for the last plane was being moved
to the start of the contone data for the next 32 lines of output. Seen
with -sDEVICE=pkmraw -dUsePlanarBuffer J8_landscape.ps but any landscape
image could have the problem. New code moves all planes and only resets
the ht_landscape parameters after all planes have been processed and
output (via copy_planes).

1 files changed, 23 insertions, 44 deletions

diff --git a/gs/base/gxht_thresh.c b/gs/base/gxht_thresh.c
index 2839507d2..d4ef95ff1 100644
--- a/gs/base/gxht_thresh.c
+++ b/gs/base/gxht_thresh.c
@@ -804,13 +804,11 @@ reset_landscape_buffer(ht_landscape_info_t *ht_landscape, byte *contone_align,
                        int data_length, int num_used)
 {
     int k;
-    int position_curr, position_new, delta;
+    int delta;
     int curr_x_pos = ht_landscape->xstart;
 
     if (ht_landscape->index < 0) {
         /* Moving right to left, move column to far right */
-        position_curr = ht_landscape->curr_pos + 1;
-        position_new = LAND_BITS-1;
         delta = ht_landscape->count - num_used;
         memset(&(ht_landscape->widths[0]), 0, sizeof(int)*LAND_BITS);
         ht_landscape->widths[LAND_BITS-1] = delta;
@@ -818,8 +816,6 @@ reset_landscape_buffer(ht_landscape_info_t *ht_landscape, byte *contone_align,
         ht_landscape->xstart = curr_x_pos - num_used;
     } else {
         /* Moving left to right, move column to far left */
-        position_curr = ht_landscape->curr_pos - 1;
-        position_new = 0;
         delta = ht_landscape->count - num_used;
         memset(&(ht_landscape->widths[0]), 0, sizeof(int)*LAND_BITS);
         ht_landscape->widths[0] = delta;
@@ -828,11 +824,6 @@ reset_landscape_buffer(ht_landscape_info_t *ht_landscape, byte *contone_align,
     }
     ht_landscape->count = delta;
     ht_landscape->num_contones = 1;
-    for (k = 0; k < data_length; k++) {
-            contone_align[position_new] = contone_align[position_curr];
-            position_curr += LAND_BITS;
-            position_new += LAND_BITS;
-    }
 }
 
 /* This performs a thresholding operation on multiple planes of data and
@@ -864,7 +855,6 @@ gxht_thresh_planes(gx_image_enum *penum, fixed xrun,
     gx_color_index dev_white = gx_device_white(dev);
     gx_color_index dev_black = gx_device_black(dev);
     bool done = false;
-    bool allow_reset = false; /* Init to silence compiler warnings */
     int spp_out = dev->color_info.num_components;
     byte *contone_align = NULL; /* Init to silence compiler warnings */
 
@@ -875,7 +865,6 @@ gxht_thresh_planes(gx_image_enum *penum, fixed xrun,
     /* Figure out the tile steps.  Left offset, Number of tiles, Right offset. */
     switch (posture) {
         case image_portrait:
-            allow_reset = true;
             vdi = penum->hci;
             /*  Iterate over the vdi and fill up our threshold buffer.  We
                  also need to loop across the planes of data */
@@ -997,11 +986,6 @@ gxht_thresh_planes(gx_image_enum *penum, fixed xrun,
                     /* Point to the proper contone data */
                     contone_align = penum->line + offset_contone[j] +
                                       LAND_BITS * j * contone_stride;
-                    if (j == spp_out - 1) {
-                        allow_reset = true;
-                    } else {
-                        allow_reset = false;
-                    }
                     if (penum->ht_landscape.offset_set) {
                         width = offset_bits;
                     } else {
@@ -1075,6 +1059,14 @@ gxht_thresh_planes(gx_image_enum *penum, fixed xrun,
                         gx_ht_threshold_landscape(contone_align, thresh_align,
                                             penum->ht_landscape, halftone, dest_height);
                     }
+                    /* We may have a line left over that has to be maintained
+                       due to line replication in the resolution conversion. */
+                    if (width != penum->ht_landscape.count) {
+                        /* move the line do not reset the stuff */
+                        move_landscape_buffer(&(penum->ht_landscape),
+                                              contone_align, dest_height);
+                    }
+                    done = true;
                 }
                 /* Perform the copy mono */
                 if (penum->ht_landscape.index < 0) {
@@ -1112,36 +1104,23 @@ gxht_thresh_planes(gx_image_enum *penum, fixed xrun,
                                                      penum->ht_plane_height);
                     }
                 }
-                /* Clean up and reset our buffer.  We may have a line left
-                   over that has to be maintained due to line replication in the
-                   resolution conversion.  However, pay attention to the reset
-                   flag which indicates we are done with our last plane */
-                if (!allow_reset) {
-                    if (width != penum->ht_landscape.count) {
-                        /* move the line do not reset the stuff */
-                        move_landscape_buffer(&(penum->ht_landscape), 
-                                              contone_align, dest_height);
-                    }
-                    done = true;
+                penum->ht_landscape.offset_set = false;
+                if (width != penum->ht_landscape.count) {
+                    reset_landscape_buffer(&(penum->ht_landscape),
+                                           contone_align, dest_height,
+                                           width);
                 } else {
-                    penum->ht_landscape.offset_set = false;
-                    if (width != penum->ht_landscape.count) {
-                        reset_landscape_buffer(&(penum->ht_landscape), 
-                                               contone_align, dest_height, 
-                                               width);
+                    /* Reset the whole buffer */
+                    penum->ht_landscape.count = 0;
+                    if (penum->ht_landscape.index < 0) {
+                        /* Going right to left */
+                        penum->ht_landscape.curr_pos = LAND_BITS-1;
                     } else {
-                        /* Reset the whole buffer */
-                        penum->ht_landscape.count = 0;
-                        if (penum->ht_landscape.index < 0) {
-                            /* Going right to left */
-                            penum->ht_landscape.curr_pos = LAND_BITS-1;
-                        } else {
-                            /* Going left to right */
-                            penum->ht_landscape.curr_pos = 0;
-                        }
-                        penum->ht_landscape.num_contones = 0;
-                        memset(&(penum->ht_landscape.widths[0]), 0, sizeof(int)*LAND_BITS);
+                        /* Going left to right */
+                        penum->ht_landscape.curr_pos = 0;
                     }
+                    penum->ht_landscape.num_contones = 0;
+                    memset(&(penum->ht_landscape.widths[0]), 0, sizeof(int)*LAND_BITS);
                 }
             }
             break;