Roll skia/third_party/skcms 5cbdc0a..011b614 (1 commits)

https://skia.googlesource.com/skcms.git/+log/5cbdc0a..011b614

2018-04-24 mtklein@chromium.org gut TF13


The AutoRoll server is located here: https://skcms-skia-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.



TBR=stani@google.com

Change-Id: I87e281fc5ac75f11acdcf7d4621d6635836b7a67
Reviewed-on: https://skia-review.googlesource.com/123393
Reviewed-by: skcms-skia-autoroll <skcms-skia-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: skcms-skia-autoroll <skcms-skia-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>

8 files changed, 3 insertions, 130 deletions

diff --git a/third_party/skcms/skcms.c b/third_party/skcms/skcms.c
index b61063cdea..0fe2c7d1a0 100644
--- a/third_party/skcms/skcms.c
+++ b/third_party/skcms/skcms.c
@@ -11,6 +11,5 @@
 #include "src/ICCProfile.c"
 #include "src/LinearAlgebra.c"
 #include "src/PortableMath.c"
-#include "src/TF13.c"
 #include "src/TransferFunction.c"
 #include "src/Transform.c"
diff --git a/third_party/skcms/skcms.h b/third_party/skcms/skcms.h
index 9c25b1d538..54c9e8ebae 100644
--- a/third_party/skcms/skcms.h
+++ b/third_party/skcms/skcms.h
@@ -73,12 +73,6 @@ typedef struct skcms_A2B {
     skcms_Curve     output_curves[3];
 } skcms_A2B;
 
-// A specialized approximation for transfer functions with gamma between 1 and 3.
-//     f(x) = sign(x) * (A|x|^3 + B|x|^2 + (1-A-B)|x|)
-typedef struct skcms_TF13 {
-    float A,B;
-} skcms_TF13;
-
 typedef struct skcms_ICCProfile {
     const uint8_t* buffer;
 
@@ -103,10 +97,6 @@ typedef struct skcms_ICCProfile {
     // and has_A2B to true.
     bool                   has_A2B;
     skcms_A2B              A2B;
-
-    // If has_trc, we may be able to approximate the curves more efficiently.
-    bool   has_tf13[3];
-    skcms_TF13 tf13[3];
 } skcms_ICCProfile;
 
 // The sRGB color profile is so commonly used that we offer a canonical skcms_ICCProfile for it.
@@ -131,8 +121,6 @@ void skcms_OptimizeForSpeed(skcms_ICCProfile*);
 bool skcms_ApproximateCurve(const skcms_Curve* curve, skcms_TransferFunction* approx,
                             float* max_error);
 
-bool skcms_ApproximateCurve13(const skcms_Curve* curve, skcms_TF13* approx, float* max_error);
-
 // What is the best single transfer function to use for the given profile? Note that there is
 // no real upper bound on the error of this transfer function.
 skcms_TransferFunction skcms_BestSingleCurve(const skcms_ICCProfile*);
diff --git a/third_party/skcms/src/ICCProfile.c b/third_party/skcms/src/ICCProfile.c
index 3c3e02abde..88b419d931 100644
--- a/third_party/skcms/src/ICCProfile.c
+++ b/third_party/skcms/src/ICCProfile.c
@@ -782,11 +782,8 @@ bool skcms_Parse(const void* buf, size_t len, skcms_ICCProfile* profile) {
 }
 
 void skcms_OptimizeForSpeed(skcms_ICCProfile* profile) {
-    // If we can approximate any of the TRC curves with a skcms_TF13, do so.
-    for (int i = 0; profile->has_trc && i < 3; i++) {
-        float err;
-        profile->has_tf13[i] = skcms_ApproximateCurve13(&profile->trc[i], &profile->tf13[i], &err);
-    }
+    (void)profile;
+    // TODO
 }
 
 const skcms_ICCProfile skcms_sRGB_profile = {
diff --git a/third_party/skcms/src/TF13.c b/third_party/skcms/src/TF13.c
deleted file mode 100644
index f6bdb3eb70..0000000000
--- a/third_party/skcms/src/TF13.c
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * Copyright 2018 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "../skcms.h"
-#include "GaussNewton.h"
-#include "PortableMath.h"
-#include <assert.h>
-#include <limits.h>
-#include <stdlib.h>
-
-// Evaluating skcms_TF13{A,B} at x:
-//   f(x) = Ax^3 + Bx^2 + (1-A-B)x
-//
-//   ∂f/∂A = x^3 - x
-//   ∂f/∂B = x^2 - x
-
-static float eval_13(float x, const void* ctx, const float P[4]) {
-    (void)ctx;
-    return x*(x*(x*P[0] + P[1]) + (1 - P[0] - P[1]));
-}
-static void grad_13(float x, const void* ctx, const float P[4], float dfdP[4]) {
-    (void)ctx;
-    (void)P;
-    dfdP[0] = x*(x*x - 1);
-    dfdP[1] = x*(x   - 1);
-}
-
-bool skcms_ApproximateCurve13(const skcms_Curve* curve, skcms_TF13* approx, float* max_error) {
-    // Start a guess at skcms_TF13{0,1}, i.e. f(x) = x^2, i.e. gamma = 2.
-    // TODO: guess better somehow, like we do in skcms_ApproximateCurve()?
-    float P[4] = { 0,1, 0,0 };
-
-    if (curve->table_entries > (uint32_t)INT_MAX) {
-        // That's just crazy.
-        return false;
-    }
-    const int N = curve->table_entries == 0 ? 257 /*TODO: tune?*/
-                                            : (int)curve->table_entries;
-
-    for (int i = 0; i < 3/*TODO: Tune???*/; i++) {
-        if (!skcms_gauss_newton_step(skcms_eval_curve, curve,
-                                     eval_13, NULL,
-                                     grad_13, NULL,
-                                     P,
-                                     0,1,N)) {
-            return false;
-        }
-    }
-
-    *max_error = 0;
-    for (int i = 0; i < N; i++) {
-        float x = i * (1.0f / (N-1));
-
-        const float got  = eval_13(x,NULL,P),
-                    want = skcms_eval_curve(x, curve);
-
-        const float err = fabsf_(got - want);
-        if (err > *max_error) {
-            *max_error = err;
-        }
-
-        assert( isfinitef_(want) );
-        if (!isfinitef_(got)) {
-            return false;
-        }
-
-        // Compare what bytes we'd choose for these floats, rounded, and scaled by 255,
-        // but intentionally not clamped... if this goes negative, we want it to hurt.
-
-        const int gbyte = (int)(255.0f * got  + 0.5f),
-                  wbyte = (int)(255.0f * want + 0.5f);
-
-        // Allow no more than 1/256 error, and no error at all at the beginning or end.
-        const int tol = (i == 0 || i == N-1) ? 0
-                                             : 1;
-        if (abs(gbyte - wbyte) > tol) {
-            return false;
-        }
-    }
-
-    approx->A = P[0];
-    approx->B = P[1];
-    return true;
-}
diff --git a/third_party/skcms/src/Transform.c b/third_party/skcms/src/Transform.c
index 9bb1ccda99..7238488399 100644
--- a/third_party/skcms/src/Transform.c
+++ b/third_party/skcms/src/Transform.c
@@ -320,11 +320,6 @@ typedef struct {
     const void* arg;
 } OpAndArg;
 
-static OpAndArg select_tf13_op(const skcms_TF13* tf, int channel) {
-    static const Op ops[] = { Op_tf13_r, Op_tf13_g, Op_tf13_b };
-    return (OpAndArg){ ops[channel], tf };
-}
-
 static OpAndArg select_curve_op(const skcms_Curve* curve, int channel) {
     static const struct { Op parametric, table_8, table_16; } ops[] = {
         { Op_tf_r, Op_table_8_r, Op_table_16_r },
@@ -524,13 +519,8 @@ bool skcms_Transform(const void*             src,
 
         } else if (srcProfile->has_trc && srcProfile->has_toXYZD50) {
             for (int i = 0; i < 3; i++) {
-                // Favor Op_noop (identity curve) over anything else,
-                // and select_tf_op() over over select_curve_op() when possible.
                 OpAndArg oa = select_curve_op(&srcProfile->trc[i], i);
                 if (oa.op != Op_noop) {
-                    if (srcProfile->has_tf13[i]) {
-                        oa = select_tf13_op(&srcProfile->tf13[i], i);
-                    }
                     *ops++  = oa.op;
                     *args++ = oa.arg;
                 }
diff --git a/third_party/skcms/src/Transform.h b/third_party/skcms/src/Transform.h
index feb0dbca2a..1c4c15b4e3 100644
--- a/third_party/skcms/src/Transform.h
+++ b/third_party/skcms/src/Transform.h
@@ -34,9 +34,6 @@
     M(tf_g)           \
     M(tf_b)           \
     M(tf_a)           \
-    M(tf13_r)         \
-    M(tf13_g)         \
-    M(tf13_b)         \
     M(table_8_r)      \
     M(table_8_g)      \
     M(table_8_b)      \
diff --git a/third_party/skcms/src/Transform_inl.h b/third_party/skcms/src/Transform_inl.h
index a3e6f2b729..3f2ac3ea96 100644
--- a/third_party/skcms/src/Transform_inl.h
+++ b/third_party/skcms/src/Transform_inl.h
@@ -246,12 +246,6 @@ SI ATTR F NS(apply_transfer_function_)(const skcms_TransferFunction* tf, F x) {
 }
 #define apply_transfer_function NS(apply_transfer_function_)
 
-SI ATTR F NS(apply_tf13_)(const skcms_TF13* tf, F x) {
-    F sign = (F)if_then_else(x < 0, -F1, F1);
-    return x*(x*(x*tf->A + sign*tf->B) + (1 - tf->A - tf->B) );
-}
-#define apply_tf13 NS(apply_tf13_)
-
 // Strided loads and stores of N values, starting from p.
 #if N == 1
     #define LOAD_3(T, p) (T)(p)[0]
@@ -853,10 +847,6 @@ static void NS(exec_ops)(const Op* ops, const void** args,
             case Op_tf_b:{ b = apply_transfer_function(*args++, b); } break;
             case Op_tf_a:{ a = apply_transfer_function(*args++, a); } break;
 
-            case Op_tf13_r:{ r = apply_tf13(*args++, r); } break;
-            case Op_tf13_g:{ g = apply_tf13(*args++, g); } break;
-            case Op_tf13_b:{ b = apply_tf13(*args++, b); } break;
-
             case Op_table_8_r: { r = NS(table_8_ )(*args++, r); } break;
             case Op_table_8_g: { g = NS(table_8_ )(*args++, g); } break;
             case Op_table_8_b: { b = NS(table_8_ )(*args++, b); } break;
diff --git a/third_party/skcms/version.sha1 b/third_party/skcms/version.sha1
index 8877d580b8..a0b9867ce7 100755
--- a/third_party/skcms/version.sha1
+++ b/third_party/skcms/version.sha1
@@ -1 +1 @@
-5cbdc0acf72bc4031f409516fbeb50e254ba638b
\ No newline at end of file
+011b61429dcc624f7e9a2d6fd39a3dbfb92c40a9
\ No newline at end of file