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authorDavid Luevano Alvarado <david@luevano.xyz>2022-05-31 21:11:46 -0600
committerDavid Luevano Alvarado <david@luevano.xyz>2022-05-31 21:11:46 -0600
commit227095a4f710ac6afd43f0a7e8b296f188cf20be (patch)
treee2f7e6a323ca4cad92b6a6012ed01a1afaf517fa /src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw
parentbd197168c39551c3456099ed2a39375a8442483f (diff)
add working gif maker
Diffstat (limited to 'src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw')
-rw-r--r--src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/LICENSE21
-rw-r--r--src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitpacker.gd31
-rw-r--r--src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitunpacker.gd41
-rw-r--r--src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lzw.gd210
4 files changed, 303 insertions, 0 deletions
diff --git a/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/LICENSE b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/LICENSE
new file mode 100644
index 0000000..ca5b2ad
--- /dev/null
+++ b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 Igor Santarek
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitpacker.gd b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitpacker.gd
new file mode 100644
index 0000000..3141d09
--- /dev/null
+++ b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitpacker.gd
@@ -0,0 +1,31 @@
+extends Reference
+
+
+class LSBLZWBitPacker:
+ var bit_index: int = 0
+ var stream: int = 0
+
+ var chunks: PoolByteArray = PoolByteArray([])
+
+ func put_byte():
+ chunks.append(stream & 0xff)
+ bit_index -= 8
+ stream >>= 8
+
+ func write_bits(value: int, bits_count: int) -> void:
+ value &= (1 << bits_count) - 1
+ value <<= bit_index
+ stream |= value
+ bit_index += bits_count
+ while bit_index >= 8:
+ self.put_byte()
+
+ func pack() -> PoolByteArray:
+ if bit_index != 0:
+ self.put_byte()
+ return chunks
+
+ func reset() -> void:
+ bit_index = 0
+ stream = 0
+ chunks = PoolByteArray([])
diff --git a/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitunpacker.gd b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitunpacker.gd
new file mode 100644
index 0000000..9f8507f
--- /dev/null
+++ b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lsbbitunpacker.gd
@@ -0,0 +1,41 @@
+extends Reference
+
+
+class LSBLZWBitUnpacker:
+ var chunk_stream: PoolByteArray
+ var bit_index: int = 0
+ var byte: int
+ var byte_index: int = 0
+
+ func _init(_chunk_stream: PoolByteArray):
+ chunk_stream = _chunk_stream
+ self.get_byte()
+
+ func get_bit(value: int, index: int) -> int:
+ return (value >> index) & 1
+
+ func set_bit(value: int, index: int) -> int:
+ return value | (1 << index)
+
+ func get_byte():
+ byte = chunk_stream[byte_index]
+ byte_index += 1
+ bit_index = 0
+
+ func read_bits(bits_count: int) -> int:
+ var result: int = 0
+ var result_bit_index: int = 0
+
+ for _i in range(bits_count):
+ if self.get_bit(byte, bit_index) == 1:
+ result = self.set_bit(result, result_bit_index)
+ result_bit_index += 1
+ bit_index += 1
+
+ if bit_index == 8:
+ self.get_byte()
+
+ return result
+
+ func remove_bits(bits_count: int) -> void:
+ self.read_bits(bits_count)
diff --git a/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lzw.gd b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lzw.gd
new file mode 100644
index 0000000..9140e7c
--- /dev/null
+++ b/src/addons/GifMaker/godot-gdgifexporter/gdgifexporter/gif-lzw/lzw.gd
@@ -0,0 +1,210 @@
+extends Reference
+
+var lsbbitpacker = preload("./lsbbitpacker.gd")
+var lsbbitunpacker = preload("./lsbbitunpacker.gd")
+
+
+class CodeEntry:
+ var sequence: PoolByteArray
+ var raw_array: Array
+
+ func _init(_sequence):
+ raw_array = _sequence
+ sequence = _sequence
+
+ func add(other):
+ return CodeEntry.new(self.raw_array + other.raw_array)
+
+ func to_string():
+ var result: String = ""
+ for element in self.sequence:
+ result += str(element) + ", "
+ return result.substr(0, result.length() - 2)
+
+
+class CodeTable:
+ var entries: Dictionary = {}
+ var counter: int = 0
+ var lookup: Dictionary = {}
+
+ func add(entry) -> int:
+ self.entries[self.counter] = entry
+ self.lookup[entry.raw_array] = self.counter
+ counter += 1
+ return counter
+
+ func find(entry) -> int:
+ return self.lookup.get(entry.raw_array, -1)
+
+ func has(entry) -> bool:
+ return self.find(entry) != -1
+
+ func get(index) -> CodeEntry:
+ return self.entries.get(index, null)
+
+ func to_string() -> String:
+ var result: String = "CodeTable:\n"
+ for id in self.entries:
+ result += str(id) + ": " + self.entries[id].to_string() + "\n"
+ result += "Counter: " + str(self.counter) + "\n"
+ return result
+
+
+func log2(value: float) -> float:
+ return log(value) / log(2.0)
+
+
+func get_bits_number_for(value: int) -> int:
+ if value == 0:
+ return 1
+ return int(ceil(log2(value + 1)))
+
+
+func initialize_color_code_table(colors: PoolByteArray) -> CodeTable:
+ var result_code_table: CodeTable = CodeTable.new()
+ for color_id in colors:
+ # warning-ignore:return_value_discarded
+ result_code_table.add(CodeEntry.new([color_id]))
+ # move counter to the first available compression code index
+ var last_color_index: int = colors.size() - 1
+ var clear_code_index: int = pow(2, get_bits_number_for(last_color_index))
+ result_code_table.counter = clear_code_index + 2
+ return result_code_table
+
+
+# compression and decompression done with source:
+# http://www.matthewflickinger.com/lab/whatsinagif/lzw_image_data.asp
+
+
+func compress_lzw(image: PoolByteArray, colors: PoolByteArray) -> Array:
+ # Initialize code table
+ var code_table: CodeTable = initialize_color_code_table(colors)
+ # Clear Code index is 2**<code size>
+ # <code size> is the amount of bits needed to write down all colors
+ # from color table. We use last color index because we can write
+ # all colors (for example 16 colors) with indexes from 0 to 15.
+ # Number 15 is in binary 0b1111, so we'll need 4 bits to write all
+ # colors down.
+ var last_color_index: int = colors.size() - 1
+ var clear_code_index: int = pow(2, get_bits_number_for(last_color_index))
+ var index_stream: PoolByteArray = image
+ var current_code_size: int = get_bits_number_for(clear_code_index)
+ var binary_code_stream = lsbbitpacker.LSBLZWBitPacker.new()
+
+ # initialize with Clear Code
+ binary_code_stream.write_bits(clear_code_index, current_code_size)
+
+ # Read first index from index stream.
+ var index_buffer: CodeEntry = CodeEntry.new([index_stream[0]])
+ var data_index: int = 1
+ # <LOOP POINT>
+ while data_index < index_stream.size():
+ # Get the next index from the index stream.
+ var k: CodeEntry = CodeEntry.new([index_stream[data_index]])
+ data_index += 1
+ # Is index buffer + k in our code table?
+ var new_index_buffer: CodeEntry = index_buffer.add(k)
+ if code_table.has(new_index_buffer): # if YES
+ # Add k to the end of the index buffer
+ index_buffer = new_index_buffer
+ else: # if NO
+ # Add a row for index buffer + k into our code table
+ binary_code_stream.write_bits(code_table.find(index_buffer), current_code_size)
+
+ # We don't want to add new code to code table if we've exceeded 4095
+ # index.
+ var last_entry_index: int = code_table.counter - 1
+ if last_entry_index != 4095:
+ # Output the code for just the index buffer to our code stream
+ # warning-ignore:return_value_discarded
+ code_table.add(new_index_buffer)
+ else:
+ # if we exceeded 4095 index (code table is full), we should
+ # output Clear Code and reset everything.
+ binary_code_stream.write_bits(clear_code_index, current_code_size)
+ code_table = initialize_color_code_table(colors)
+ # get_bits_number_for(clear_code_index) is the same as
+ # LZW code size + 1
+ current_code_size = get_bits_number_for(clear_code_index)
+
+ # Detect when you have to save new codes in bigger bits boxes
+ # change current code size when it happens because we want to save
+ # flexible code sized codes
+ var new_code_size_candidate: int = get_bits_number_for(code_table.counter - 1)
+ if new_code_size_candidate > current_code_size:
+ current_code_size = new_code_size_candidate
+
+ # Index buffer is set to k
+ index_buffer = k
+ # Output code for contents of index buffer
+ binary_code_stream.write_bits(code_table.find(index_buffer), current_code_size)
+
+ # output end with End Of Information Code
+ binary_code_stream.write_bits(clear_code_index + 1, current_code_size)
+
+ var min_code_size: int = get_bits_number_for(clear_code_index) - 1
+
+ return [binary_code_stream.pack(), min_code_size]
+
+
+# gdlint: ignore=max-line-length
+func decompress_lzw(code_stream_data: PoolByteArray, min_code_size: int, colors: PoolByteArray) -> PoolByteArray:
+ var code_table: CodeTable = initialize_color_code_table(colors)
+ var index_stream: PoolByteArray = PoolByteArray([])
+ var binary_code_stream = lsbbitunpacker.LSBLZWBitUnpacker.new(code_stream_data)
+ var current_code_size: int = min_code_size + 1
+ var clear_code_index: int = pow(2, min_code_size)
+
+ # CODE is an index of code table, {CODE} is sequence inside
+ # code table with index CODE. The same goes for PREVCODE.
+
+ # Remove first Clear Code from stream. We don't need it.
+ binary_code_stream.remove_bits(current_code_size)
+
+ # let CODE be the first code in the code stream
+ var code: int = binary_code_stream.read_bits(current_code_size)
+ # output {CODE} to index stream
+ index_stream.append_array(code_table.get(code).sequence)
+ # set PREVCODE = CODE
+ var prevcode: int = code
+ # <LOOP POINT>
+ while true:
+ # let CODE be the next code in the code stream
+ code = binary_code_stream.read_bits(current_code_size)
+ # Detect Clear Code. When detected reset everything and get next code.
+ if code == clear_code_index:
+ code_table = initialize_color_code_table(colors)
+ current_code_size = min_code_size + 1
+ code = binary_code_stream.read_bits(current_code_size)
+ elif code == clear_code_index + 1: # Stop when detected EOI Code.
+ break
+ # is CODE in the code table?
+ var code_entry: CodeEntry = code_table.get(code)
+ if code_entry != null: # if YES
+ # output {CODE} to index stream
+ index_stream.append_array(code_entry.sequence)
+ # let k be the first index in {CODE}
+ var k: CodeEntry = CodeEntry.new([code_entry.sequence[0]])
+ # warning-ignore:return_value_discarded
+ # add {PREVCODE} + k to the code table
+ code_table.add(code_table.get(prevcode).add(k))
+ # set PREVCODE = CODE
+ prevcode = code
+ else: # if NO
+ # let k be the first index of {PREVCODE}
+ var prevcode_entry: CodeEntry = code_table.get(prevcode)
+ var k: CodeEntry = CodeEntry.new([prevcode_entry.sequence[0]])
+ # output {PREVCODE} + k to index stream
+ index_stream.append_array(prevcode_entry.add(k).sequence)
+ # add {PREVCODE} + k to code table
+ # warning-ignore:return_value_discarded
+ code_table.add(prevcode_entry.add(k))
+ # set PREVCODE = CODE
+ prevcode = code
+
+ # Detect when we should increase current code size and increase it.
+ var new_code_size_candidate: int = get_bits_number_for(code_table.counter)
+ if new_code_size_candidate > current_code_size:
+ current_code_size = new_code_size_candidate
+
+ return index_stream