diff options
Diffstat (limited to 'indra/llimage/llimagej2c.cpp')
| -rw-r--r-- | indra/llimage/llimagej2c.cpp | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/indra/llimage/llimagej2c.cpp b/indra/llimage/llimagej2c.cpp index aa161709a1..5a941dc958 100644 --- a/indra/llimage/llimagej2c.cpp +++ b/indra/llimage/llimagej2c.cpp @@ -281,10 +281,11 @@ S32 LLImageJ2C::calcDataSizeJ2C(S32 w, S32 h, S32 comp, S32 discard_level, F32 r S32 height = (h > 0) ? h : 2048; S32 max_dimension = llmax(width, height); // Find largest dimension S32 block_area = MAX_BLOCK_SIZE * MAX_BLOCK_SIZE; // Calculated initial block area from established max block size (currently 64) - block_area *= llmax((max_dimension / MAX_BLOCK_SIZE / max_components), 1); // Adjust initial block area by ratio of largest dimension to block size per component - S32 totalbytes = (S32) (block_area * max_components * precision); // First block layer computed before loop without compression rate - S32 block_layers = 1; // Start at layer 1 since first block layer is computed outside loop - while (block_layers < 6) // Walk five layers for the five discards in JPEG2000 + S32 max_layers = (S32)llmax(llround(log2f((float)max_dimension) - log2f((float)MAX_BLOCK_SIZE)), 4); // Find number of powers of two between extents and block size to a minimum of 4 + block_area *= llmax(max_layers, 1); // Adjust initial block area by max number of layers + S32 totalbytes = (S32) (MIN_LAYER_SIZE * max_components * precision); // Start estimation with a minimum reasonable size + S32 block_layers = 0; + while (block_layers <= max_layers) // Walk the layers { if (block_layers <= (5 - discard_level)) // Walk backwards from discard 5 to required discard layer. totalbytes += (S32) (block_area * max_components * precision * rate); // Add each block layer reduced by assumed compression rate |