diff options
Diffstat (limited to '')
| -rw-r--r-- | src/icc.py | 31 |
1 files changed, 15 insertions, 16 deletions
@@ -123,28 +123,32 @@ def parse_icc(content): @param n:int The number of bytes to read @return :list<int> The next `n` bytes of the profile ''' - if len(content) < n: + nonlocal ptr + if len(content) - ptr < n: raise Exception('Premature end of file: %s' % pathname) - rc, content[:] = content[:n], content[n:] + rc = = content[ptr : ptr + n] + ptr += n return rc # Convert profile encoding format for bytes to integer list - content = list(content) + content, ptr = list(content), 0 # Skip the first 128 bytes read(128) - # Get the number of bytes - n_tags, ptr = int_(read(4)), 128 + 4 + # Get the number of tags + n_tags = int_(read(4)) # Create array for the lookup tables to create R_curve, G_curve, B_curve = [], [], [] + xptr = ptr for i_tag in range(n_tags): # Get profile encoding type, offset to the profile and the encoding size of its data - (tag_name, tag_offset, tag_size), ptr = [int_(read(4)) for _ in range(3)], ptr + 3 * 4 - # XXX should I not jump to the data now instead of inside the if statements' bodies? + ptr = xptr + (tag_name, tag_offset, tag_size) = [int_(read(4)) for _ in range(3)] + xptr = ptr + # Jump to the profile data + ptr = tag_offset if tag_name == MLUT_TAG: ## The profile is encododed as an dual-byte precision lookup table - # Jump to the profile data - read(tag_offset - ptr) # Get the lookup table for the red channel, for _ in range(256): R_curve.append(int_(read(2)) / 65535) # for the green channel @@ -155,12 +159,10 @@ def parse_icc(content): elif tag_name == VCGT_TAG: ## The profile is encoded as with gamma, brightness and contrast values # or as a variable precision lookup table profile - # Jump to the profile data - read(tag_offset - ptr) # VCGT profiles starts where their magic number tag_name = int_(read(4)) if not tag_name == VCGT_TAG: - break + continue # Skip four bytes read(4) # and get the actual encoding type @@ -172,7 +174,7 @@ def parse_icc(content): (n_channels, n_entries, entry_size) = 3, 256, 2 if not n_channels == 3: # Assuming sRGB, can only be an correct assumption if there are exactly three channels - break + continue # Calculate the divisor for mapping to [0, 1] divisor = (256 ** entry_size) - 1 # Values are encoded in integer form with `entry_size` bytes @@ -201,9 +203,6 @@ def parse_icc(content): # before brightness and contrast rgb_limits(r_min, r_max, g_min, g_max, b_min, b_max) return f - break - # XXX should I not jump to (tag_offset + tag_size - ptr) here - # and not break the loops when unknown? raise Exception('Unsupported ICC profile file') |