Irreversible decoding: align code more closely to the standard by avoid messing up with stepsize (no functional change)

2 files changed, 10 insertions, 8 deletions

diff --git a/src/lib/openjp2/t1.c b/src/lib/openjp2/t1.c
index 8d5feadf..0787dce8 100644
--- a/src/lib/openjp2/t1.c
+++ b/src/lib/openjp2/t1.c
@@ -1725,10 +1725,11 @@ static void opj_t1_clbl_decode_processor(void* user_data, opj_tls_t* tls)
                 datap[i] /= 2;
             }
         } else {        /* if (tccp->qmfbid == 0) */
+            const float stepsize = 0.5f * band->stepsize;
             i = 0;
 #ifdef __SSE2__
             {
-                const __m128 xmm_stepsize = _mm_set1_ps(band->stepsize);
+                const __m128 xmm_stepsize = _mm_set1_ps(stepsize);
                 for (; i < (cblk_size & ~15U); i += 16) {
                     __m128 xmm0_data = _mm_cvtepi32_ps(_mm_load_si128((__m128i * const)(
                                                            datap + 0)));
@@ -1747,7 +1748,7 @@ static void opj_t1_clbl_decode_processor(void* user_data, opj_tls_t* tls)
             }
 #endif
             for (; i < cblk_size; ++i) {
-                OPJ_FLOAT32 tmp = ((OPJ_FLOAT32)(*datap)) * band->stepsize;
+                OPJ_FLOAT32 tmp = ((OPJ_FLOAT32)(*datap)) * stepsize;
                 memcpy(datap, &tmp, sizeof(tmp));
                 datap++;
             }
@@ -1773,12 +1774,13 @@ static void opj_t1_clbl_decode_processor(void* user_data, opj_tls_t* tls)
             }
         }
     } else {        /* if (tccp->qmfbid == 0) */
+        const float stepsize = 0.5f * band->stepsize;
         OPJ_FLOAT32* OPJ_RESTRICT tiledp = (OPJ_FLOAT32*) &tilec->data[(OPJ_SIZE_T)y *
                                                          tile_w + (OPJ_SIZE_T)x];
         for (j = 0; j < cblk_h; ++j) {
             OPJ_FLOAT32* OPJ_RESTRICT tiledp2 = tiledp;
             for (i = 0; i < cblk_w; ++i) {
-                OPJ_FLOAT32 tmp = (OPJ_FLOAT32) * datap * band->stepsize;
+                OPJ_FLOAT32 tmp = (OPJ_FLOAT32) * datap * stepsize;
                 *tiledp2 = tmp;
                 datap++;
                 tiledp2++;
diff --git a/src/lib/openjp2/tcd.c b/src/lib/openjp2/tcd.c
index e41e7772..a84ec063 100644
--- a/src/lib/openjp2/tcd.c
+++ b/src/lib/openjp2/tcd.c
@@ -112,7 +112,7 @@ void tcd_dump(FILE *fd, opj_tcd_t *tcd, opj_tcd_image_t * img)
  * Initializes tile coding/decoding
  */
 static INLINE OPJ_BOOL opj_tcd_init_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
-        OPJ_BOOL isEncoder, OPJ_FLOAT32 fraction, OPJ_SIZE_T sizeof_block,
+        OPJ_BOOL isEncoder, OPJ_SIZE_T sizeof_block,
         opj_event_mgr_t* manager);
 
 /**
@@ -721,7 +721,7 @@ OPJ_BOOL opj_alloc_tile_component_data(opj_tcd_tilecomp_t *l_tilec)
 /* ----------------------------------------------------------------------- */
 
 static INLINE OPJ_BOOL opj_tcd_init_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
-        OPJ_BOOL isEncoder, OPJ_FLOAT32 fraction, OPJ_SIZE_T sizeof_block,
+        OPJ_BOOL isEncoder, OPJ_SIZE_T sizeof_block,
         opj_event_mgr_t* manager)
 {
     OPJ_UINT32(*l_gain_ptr)(OPJ_UINT32) = 00;
@@ -1013,7 +1013,7 @@ static INLINE OPJ_BOOL opj_tcd_init_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
                 /* Delta_b value of Equation E-3 in "E.1 Inverse quantization
                  * procedure" of the standard */
                 l_band->stepsize = (OPJ_FLOAT32)(((1.0 + l_step_size->mant / 2048.0) * pow(2.0,
-                                                  (OPJ_INT32)(numbps - l_step_size->expn)))) * fraction;
+                                                  (OPJ_INT32)(numbps - l_step_size->expn))));
                 /* Mb value of Equation E-2 in "E.1 Inverse quantization
                  * procedure" of the standard */
                 l_band->numbps = l_step_size->expn + (OPJ_INT32)l_tccp->numgbits -
@@ -1196,14 +1196,14 @@ static INLINE OPJ_BOOL opj_tcd_init_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
 OPJ_BOOL opj_tcd_init_encode_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
                                   opj_event_mgr_t* p_manager)
 {
-    return opj_tcd_init_tile(p_tcd, p_tile_no, OPJ_TRUE, 1.0F,
+    return opj_tcd_init_tile(p_tcd, p_tile_no, OPJ_TRUE,
                              sizeof(opj_tcd_cblk_enc_t), p_manager);
 }
 
 OPJ_BOOL opj_tcd_init_decode_tile(opj_tcd_t *p_tcd, OPJ_UINT32 p_tile_no,
                                   opj_event_mgr_t* p_manager)
 {
-    return opj_tcd_init_tile(p_tcd, p_tile_no, OPJ_FALSE, 0.5F,
+    return opj_tcd_init_tile(p_tcd, p_tile_no, OPJ_FALSE,
                              sizeof(opj_tcd_cblk_dec_t), p_manager);
 }