Patch by Callum Lerwick. This patch rearranges the largest memory allocations so they're allocated as late as possible, and freed as soon as possible. This cuts memory usage by about half on two large test images.

1 files changed, 12 insertions, 14 deletions

diff --git a/libopenjpeg/tcd.c b/libopenjpeg/tcd.c
index 533fd246..1303c5f8 100644
--- a/libopenjpeg/tcd.c
+++ b/libopenjpeg/tcd.c
@@ -641,7 +641,6 @@ void tcd_malloc_decode(opj_tcd_t *tcd, opj_image_t * image, opj_cp_t * cp) {
 		w = int_ceildivpow2(x1 - x0, image->comps[i].factor);
 		h = int_ceildivpow2(y1 - y0, image->comps[i].factor);
 
-		image->comps[i].data = (int *) opj_malloc(w * h * sizeof(int));
 		image->comps[i].w = w;
 		image->comps[i].h = h;
 		image->comps[i].x0 = x0;
@@ -671,8 +670,6 @@ void tcd_malloc_decode_tile(opj_tcd_t *tcd, opj_image_t * image, opj_cp_t * cp,
 		tilec->x1 = int_ceildiv(tile->x1, image->comps[compno].dx);
 		tilec->y1 = int_ceildiv(tile->y1, image->comps[compno].dy);
 
-		/* The +3 is headroom required by the vectorized DWT */
-		tilec->data = (int*) opj_aligned_malloc((((tilec->x1 - tilec->x0) * (tilec->y1 - tilec->y0))+3) * sizeof(int));
 		tilec->numresolutions = tccp->numresolutions;
 		tilec->resolutions = (opj_tcd_resolution_t *) opj_malloc(tilec->numresolutions * sizeof(opj_tcd_resolution_t));
 		
@@ -1352,7 +1349,10 @@ bool tcd_decode_tile(opj_tcd_t *tcd, unsigned char *src, int len, int tileno, op
 	t1_time = opj_clock();	/* time needed to decode a tile */
 	t1 = t1_create(tcd->cinfo);
 	for (compno = 0; compno < tile->numcomps; ++compno) {
-		t1_decode_cblks(t1, &tile->comps[compno], &tcd->tcp->tccps[compno]);
+		opj_tcd_tilecomp_t* tilec = &tile->comps[compno];
+		/* The +3 is headroom required by the vectorized DWT */
+		tilec->data = (int*) opj_aligned_malloc((((tilec->x1 - tilec->x0) * (tilec->y1 - tilec->y0))+3) * sizeof(int));
+		t1_decode_cblks(t1, tilec, &tcd->tcp->tccps[compno]);
 	}
 	t1_destroy(t1);
 	t1_time = opj_clock() - t1_time;
@@ -1423,6 +1423,9 @@ bool tcd_decode_tile(opj_tcd_t *tcd, unsigned char *src, int len, int tileno, op
 		int offset_y = int_ceildivpow2(imagec->y0, imagec->factor);
 
 		int i, j;
+		if(!imagec->data){
+			imagec->data = (int*) opj_malloc(imagec->w * imagec->h * sizeof(int));
+		}
 		if(tcd->tcp->tccps[compno].qmfbid == 1) {
 			for(j = res->y0; j < res->y1; ++j) {
 				for(i = res->x0; i < res->x1; ++i) {
@@ -1441,16 +1444,12 @@ bool tcd_decode_tile(opj_tcd_t *tcd, unsigned char *src, int len, int tileno, op
 				}
 			}
 		}
+		opj_aligned_free(tilec->data);
 	}
 
 	tile_time = opj_clock() - tile_time;	/* time needed to decode a tile */
 	opj_event_msg(tcd->cinfo, EVT_INFO, "- tile decoded in %f s\n", tile_time);
 
-	for (compno = 0; compno < tile->numcomps; compno++) {
-		opj_aligned_free(tcd->tcd_image->tiles[tileno].comps[compno].data);
-		tcd->tcd_image->tiles[tileno].comps[compno].data = NULL;
-	}
-
 	if (eof) {
 		return false;
 	}
@@ -1460,7 +1459,7 @@ bool tcd_decode_tile(opj_tcd_t *tcd, unsigned char *src, int len, int tileno, op
 
 void tcd_free_decode(opj_tcd_t *tcd) {
 	opj_tcd_image_t *tcd_image = tcd->tcd_image;	
-	if (tcd_image->tiles != NULL) opj_free(tcd_image->tiles);
+	opj_free(tcd_image->tiles);
 }
 
 void tcd_free_decode_tile(opj_tcd_t *tcd, int tileno) {
@@ -1477,15 +1476,14 @@ void tcd_free_decode_tile(opj_tcd_t *tcd, int tileno) {
 				opj_tcd_band_t *band = &res->bands[bandno];
 				for (precno = 0; precno < res->ph * res->pw; precno++) {
 					opj_tcd_precinct_t *prec = &band->precincts[precno];
-					if (prec->cblks != NULL) opj_free(prec->cblks);
 					if (prec->imsbtree != NULL) tgt_destroy(prec->imsbtree);
 					if (prec->incltree != NULL) tgt_destroy(prec->incltree);
 				}
-				if (band->precincts != NULL) opj_free(band->precincts);
+				opj_free(band->precincts);
 			}
 		}
-		if (tilec->resolutions != NULL) opj_free(tilec->resolutions);
+		opj_free(tilec->resolutions);
 	}
-	if (tile->comps != NULL) opj_free(tile->comps);
+	opj_free(tile->comps);
 }