From 2e4efefabb00a2136b47d4c35f6e7c4e2cff974e Mon Sep 17 00:00:00 2001
From: treeform <starplant@gmail.com>
Date: Thu, 5 May 2022 09:55:25 -0700
Subject: [PATCH 1/2] Add benchmarks.
---
tests/benchmark_jpeg.nim | 45 +++++++++++++++++++++++++++++++++++++---
1 file changed, 42 insertions(+), 3 deletions(-)
diff --git a/tests/benchmark_jpeg.nim b/tests/benchmark_jpeg.nim
index 3bbe13e..0558438 100644
--- a/tests/benchmark_jpeg.nim
+++ b/tests/benchmark_jpeg.nim
@@ -1,6 +1,45 @@
import benchy, pixie/fileformats/jpg
-let data = readFile("tests/fileformats/jpeg/jpeg420exif.jpg")
+var files = @[
+ "tests/fileformats/jpeg/master/red.jpg",
+ "tests/fileformats/jpeg/master/green.jpg",
+ "tests/fileformats/jpeg/master/blue.jpg",
+ "tests/fileformats/jpeg/master/white.jpg",
+ "tests/fileformats/jpeg/master/black.jpg",
-timeIt "pixie decode":
- discard decodeJpg(data)
+ "tests/fileformats/jpeg/master/8x8.jpg",
+ "tests/fileformats/jpeg/master/8x8_progressive.jpg",
+
+ "tests/fileformats/jpeg/master/16x16.jpg",
+ "tests/fileformats/jpeg/master/16x16_progressive.jpg",
+
+ "tests/fileformats/jpeg/master/quality_01.jpg",
+ "tests/fileformats/jpeg/master/quality_10.jpg",
+ "tests/fileformats/jpeg/master/quality_25.jpg",
+ "tests/fileformats/jpeg/master/quality_50.jpg",
+ "tests/fileformats/jpeg/master/quality_100.jpg",
+
+ "tests/fileformats/jpeg/master/cat_4_4_4.jpg",
+ "tests/fileformats/jpeg/master/cat_4_4_4.jpg",
+ "tests/fileformats/jpeg/master/cat_4_2_2.jpg",
+ "tests/fileformats/jpeg/master/cat_4_2_0.jpg",
+ "tests/fileformats/jpeg/master/cat_4_1_1.jpg",
+ "tests/fileformats/jpeg/master/cat_4_4_4_progressive.jpg",
+ "tests/fileformats/jpeg/master/cat_restart_markers_5.jpg",
+ "tests/fileformats/jpeg/master/cat_restart_markers_5_progressive.jpg",
+
+ "tests/fileformats/jpeg/master/mandrill.jpg",
+ "tests/fileformats/jpeg/master/exif_overrun.jpg",
+ "tests/fileformats/jpeg/master/grayscale_test.jpg",
+ "tests/fileformats/jpeg/master/progressive.jpg",
+
+ "tests/fileformats/jpeg/master/testimg.jpg",
+ "tests/fileformats/jpeg/master/testimgp.jpg",
+ "tests/fileformats/jpeg/master/testorig.jpg",
+ "tests/fileformats/jpeg/master/testprog.jpg",
+]
+
+for file in files:
+ let data = readFile(file)
+ timeIt "jpeg " & $(len(data) div 1024) & "k decode":
+ discard decodeJpg(data)
From fdd6f51ddee2b43de664cf4302299c9e1c7b3993 Mon Sep 17 00:00:00 2001
From: treeform <starplant@gmail.com>
Date: Thu, 5 May 2022 09:55:43 -0700
Subject: [PATCH 2/2] Remove table use.
---
src/pixie/fileformats/jpeg.nim | 58 +++++++++++++---------------------
1 file changed, 22 insertions(+), 36 deletions(-)
diff --git a/src/pixie/fileformats/jpeg.nim b/src/pixie/fileformats/jpeg.nim
index 955f300..bc870ae 100644
--- a/src/pixie/fileformats/jpeg.nim
+++ b/src/pixie/fileformats/jpeg.nim
@@ -1,4 +1,4 @@
-import pixie/common, pixie/images, strutils, tables
+import pixie/common, pixie/images, sequtils, strutils
# This JPEG decoder is loosely based on stb_image which is public domain.
@@ -69,6 +69,7 @@ type
dcPred: int
widthCoeff, heightCoeff: int
data, coeff, lineBuf: seq[uint8]
+ blocks: seq[seq[array[64, int16]]]
DecoderState = object
buffer: seq[uint8]
@@ -86,8 +87,6 @@ type
mcuWidth, mcuHeight, numMcuWide, numMcuHigh: int
componentOrder: seq[int]
progressive: bool
- decodedBlocks: Table[(int, int, int), array[64, int16]]
-
restartInterval: int
todo: int
eobRun: int
@@ -287,6 +286,14 @@ proc decodeSOF0(state: var DecoderState) =
state.maxXScale - 1
) div state.maxXScale
+ # Allocate block data structures.
+ state.components[i].blocks = newSeqWith(
+ state.components[i].width,
+ newSeq[array[64, int16]](
+ state.components[i].height
+ )
+ )
+
state.components[i].widthStride =
state.numMcuWide * state.components[i].yScale * 8
state.components[i].heightStride =
@@ -766,12 +773,7 @@ proc idctBlock(component: var Component, offset: int, data: array[64, int16]) =
proc decodeBlock(state: var DecoderState, comp, row, column: int) =
## Decodes a block.
- var data: array[64, int16]
- if (comp, row, column) in state.decodedBlocks:
- try:
- data = state.decodedBlocks[(comp, row, column)]
- except:
- failInvalid()
+ var data = state.components[comp].blocks[row][column]
if state.progressive:
if state.spectralStart == 0:
state.decodeProgressiveBlock(comp, data)
@@ -779,10 +781,7 @@ proc decodeBlock(state: var DecoderState, comp, row, column: int) =
state.decodeProgressiveContinuationBlock(comp, data)
else:
state.decodeRegularBlock(comp, data)
- try:
- state.decodedBlocks[(comp, row, column)] = data
- except:
- failInvalid()
+ state.components[comp].blocks[row][column] = data
template checkReset(state: var DecoderState) =
dec state.todo
@@ -807,11 +806,8 @@ proc decodeBlocks(state: var DecoderState) =
comp = state.componentOrder[0]
w = (state.components[comp].width + 7) shr 3
h = (state.components[comp].height + 7) shr 3
- for j in 0 ..< h:
- for i in 0 ..< w:
- let
- row = i * 8
- column = j * 8
+ for column in 0 ..< h:
+ for row in 0 ..< w:
state.decodeBlock(comp, row, column)
state.checkReset()
else:
@@ -822,8 +818,8 @@ proc decodeBlocks(state: var DecoderState) =
for j in 0 ..< state.components[comp].yScale:
for i in 0 ..< state.components[comp].xScale:
let
- row = (x * state.components[comp].xScale + i) * 8
- column = (y * state.components[comp].yScale + j) * 8
+ row = (x * state.components[comp].xScale + i)
+ column = (y * state.components[comp].yScale + j)
state.decodeBlock(comp, row, column)
state.checkReset()
else:
@@ -834,8 +830,8 @@ proc decodeBlocks(state: var DecoderState) =
for j in 0 ..< state.components[comp].xScale:
for i in 0 ..< state.components[comp].yScale:
let
- row = (x * state.components[comp].yScale + i) * 8
- column = (y * state.components[comp].xScale + j) * 8
+ row = (x * state.components[comp].yScale + i)
+ column = (y * state.components[comp].xScale + j)
state.decodeBlock(comp, row, column)
state.checkReset()
@@ -846,19 +842,9 @@ proc quantizationAndIDCTPass(state: var DecoderState) =
w = (state.components[comp].width + 7) shr 3
h = (state.components[comp].height + 7) shr 3
- for j in 0 ..< h:
- for i in 0 ..< w:
- let
- row = i * 8
- column = j * 8
-
- var data: array[64, int16]
-
- if (comp, row, column) in state.decodedBlocks:
- try:
- data = state.decodedBlocks[(comp, row, column)]
- except:
- failInvalid()
+ for column in 0 ..< h:
+ for row in 0 ..< w:
+ var data = state.components[comp].blocks[row][column]
for i in 0 ..< 64:
let qTableId = state.components[comp].quantizationTableId
@@ -867,7 +853,7 @@ proc quantizationAndIDCTPass(state: var DecoderState) =
data[i] = clampInt16(data[i] * state.quantizationTables[qTableId][i].int)
state.components[comp].idctBlock(
- state.components[comp].widthStride * column + row,
+ state.components[comp].widthStride * column * 8 + row * 8,
data
)