diff options
Diffstat (limited to 'src/scanner.vala')
| -rw-r--r-- | src/scanner.vala | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/src/scanner.vala b/src/scanner.vala index 67a0d96..29c729b 100644 --- a/src/scanner.vala +++ b/src/scanner.vala @@ -1333,6 +1333,10 @@ public class Scanner : Object info.width = parameters.pixels_per_line; info.height = parameters.lines; info.depth = parameters.depth; + /* Reduce bit depth if requested lower than received */ + // FIXME: This a hack and only works on 8 bit gray to 2 bit gray + if (parameters.depth == 8 && parameters.format == Sane.Frame.GRAY && job.depth == 2 && job.scan_mode == ScanMode.GRAY) + info.depth = job.depth; info.n_channels = parameters.format == Sane.Frame.GRAY ? 1 : 3; info.dpi = job.dpi; // FIXME: This is the requested DPI, not the actual DPI info.device = current_device; @@ -1472,6 +1476,56 @@ public class Scanner : Object n_used++; } + /* Reduce bit depth if requested lower than received */ + // FIXME: This a hack and only works on 8 bit gray to 2 bit gray + if (parameters.depth == 8 && parameters.format == Sane.Frame.GRAY && + job.depth == 2 && job.scan_mode == ScanMode.GRAY) + { + uchar block = 0; + var write_offset = 0; + var block_shift = 6; + for (var i = 0; i < line.n_lines; i++) + { + var offset = i * line.data_length; + for (var x = 0; x < line.width; x++) + { + var p = line.data[offset + x]; + + uchar sample; + if (p >= 192) + sample = 3; + else if (p >= 128) + sample = 2; + else if (p >= 64) + sample = 1; + else + sample = 0; + + block |= sample << block_shift; + if (block_shift == 0) + { + line.data[write_offset] = block; + write_offset++; + block = 0; + block_shift = 6; + } + else + block_shift -= 2; + } + + /* Finish each line on a byte boundary */ + if (block_shift != 6) + { + line.data[write_offset] = block; + write_offset++; + block = 0; + block_shift = 6; + } + } + + line.data_length = (line.width * 2 + 7) / 8; + } + notify_event (new NotifyGotLine (job.id, line)); } } |