status-im/nimPNG
2
0
Fork 0
mirror of https://github.com/status-im/nimPNG.git synced 2025-02-20 00:08:16 +00:00
Code Issues Projects Releases Wiki Activity

apng encoder preparation

Browse Source
This commit is contained in:
andri lim 2017-11-24 13:06:49 +07:00
parent 05cce9b58f
commit 90a1f94115
1 changed files with 43 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
nimPNG.nim
View File

@ -2132,6 +2132,9 @@ type
unknown*: seq[PNGUnknown] unknown*: seq[PNGUnknown]
# APNG number of plays, 0 = infinite
numPlays*: int
PNGColorProfile = ref object PNGColorProfile = ref object
colored: bool #not greyscale colored: bool #not greyscale
key: bool #if true, image is not opaque. Only if true and alpha is false, color key is possible. key: bool #if true, image is not opaque. Only if true and alpha is false, color key is possible.
@ -2413,9 +2416,30 @@ method writeChunk(chunk: PNGICCProfile, png: PNG): bool =
chunk.writeString zlib_compress(nz) chunk.writeString zlib_compress(nz)
result = true result = true
#method writeChunk(chunk: PNGICCProfile, png: PNG): bool = method writeChunk(chunk: APNGAnimationControl, png: PNG): bool =
#method writeChunk(chunk: PNGICCProfile, png: PNG): bool = # estimate 8 bytes
#method writeChunk(chunk: PNGICCProfile, png: PNG): bool = chunk.writeInt32(chunk.numFrames)
chunk.writeInt32(chunk.numPlays)
result = true
method writeChunk(chunk: APNGFrameControl, png: PNG): bool =
# estimate 5*4 + 2*2 + 2 = 26 bytes
chunk.writeInt32(chunk.sequenceNumber)
chunk.writeInt32(chunk.width)
chunk.writeInt32(chunk.height)
chunk.writeInt32(chunk.xOffset)
chunk.writeInt32(chunk.yOffset)
chunk.writeInt16(chunk.delayNum)
chunk.writeInt16(chunk.delayDen)
chunk.writeByte(ord(chunk.disposeOp))
chunk.writeByte(ord(chunk.blendOp))
result = true
method writeChunk(chunk: APNGFrameData, png: PNG): bool =
chunk.writeInt32(chunk.sequenceNumber)
var nz = nzDeflateInit(png.apngPixels[chunk.frameDataPos])
chunk.writeString zlib_compress(nz)
result = true
proc isGreyscaleType(mode: PNGColorMode): bool = proc isGreyscaleType(mode: PNGColorMode): bool =
result = mode.colorType in {LCT_GREY, LCT_GREY_ALPHA} result = mode.colorType in {LCT_GREY, LCT_GREY_ALPHA}
@ -3065,6 +3089,22 @@ proc addChunkIEND(png: PNG) =
var chunk = make[PNGEnd](IEND, 0) var chunk = make[PNGEnd](IEND, 0)
png.chunks.add chunk png.chunks.add chunk
proc addChunkacTL(png: PNG, numFrames, numPlays: int) =
var chunk = make[APNGAnimationControl](acTL, 8)
chunk.numFrames = numFrames
chunk.numPlays = numPlays
png.chunks.add chunk
proc addChunkfcTL(png: PNG, chunk: APNGFrameControl) =
chunk.chunkType = fcTL
if chunk.data.isNil:
chunk.data = newStringOfCap(26)
png.chunks.add chunk
proc addChunkfdAT(png: PNG, sequenceNumber, frameDataPos: int) =
var chunk = make[APNGFrameData](fdAT, 0)
png.chunks.add chunk
proc encodePNG*(input: string, w, h: int, settings = PNGEncoder(nil)): PNG = proc encodePNG*(input: string, w, h: int, settings = PNGEncoder(nil)): PNG =
var png: PNG var png: PNG
new(png) new(png)