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// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "lib/jpegli/quant.h"
#include <algorithm>
#include <cmath>
#include <vector>
#include "lib/jpegli/adaptive_quantization.h"
#include "lib/jpegli/common.h"
#include "lib/jpegli/encode_internal.h"
#include "lib/jpegli/error.h"
#include "lib/jpegli/memory_manager.h"
#include "lib/jxl/base/byte_order.h"
#include "lib/jxl/base/status.h"
namespace jpegli {
namespace {
// Global scale is chosen in a way that butteraugli 3-norm matches libjpeg
// with the same quality setting. Fitted for quality 90 on jyrki31 corpus.
constexpr float kGlobalScaleXYB = 1.43951668f;
constexpr float kGlobalScaleYCbCr = 1.73966010f;
constexpr float kBaseQuantMatrixXYB[] = {
// c = 0
7.5629935265f,
19.8247814178f,
22.5724945068f,
20.6706695557f,
22.6864585876f,
23.5696277618f,
25.8129081726f,
36.3307571411f,
19.8247814178f,
21.5503177643f,
19.9372234344f,
20.5424213409f,
21.8645496368f,
23.9041385651f,
28.2844066620f,
32.6609764099f,
22.5724945068f,
19.9372234344f,
21.9017257690f,
19.1223449707f,
21.7515811920f,
24.6724700928f,
25.4249649048f,
32.6653823853f,
20.6706695557f,
20.5424213409f,
19.1223449707f,
20.1610221863f,
25.3719692230f,
25.9668903351f,
30.9804954529f,
31.3406009674f,
22.6864585876f,
21.8645496368f,
21.7515811920f,
25.3719692230f,
26.2431850433f,
40.5992202759f,
43.2624626160f,
63.3010940552f,
23.5696277618f,
23.9041385651f,
24.6724700928f,
25.9668903351f,
40.5992202759f,
48.3026771545f,
34.0964355469f,
61.9852142334f,
25.8129081726f,
28.2844066620f,
25.4249649048f,
30.9804954529f,
43.2624626160f,
34.0964355469f,
34.4937438965f,
66.9702758789f,
36.3307571411f,
32.6609764099f,
32.6653823853f,
31.3406009674f,
63.3010940552f,
61.9852142334f,
66.9702758789f,
39.9652709961f,
// c = 1
1.6262000799f,
3.2199242115f,
3.4903779030f,
3.9148359299f,
4.8337211609f,
4.9108843803f,
5.3137121201f,
6.1676793098f,
3.2199242115f,
3.4547898769f,
3.6036829948f,
4.2652835846f,
4.8368387222f,
4.8226222992f,
5.6120514870f,
6.3431472778f,
3.4903779030f,
3.6036829948f,
3.9044559002f,
4.3374395370f,
4.8435096741f,
5.4057979584f,
5.6066360474f,
6.1075134277f,
3.9148359299f,
4.2652835846f,
4.3374395370f,
4.6064834595f,
5.1751475334f,
5.4013924599f,
6.0399808884f,
6.7825231552f,
4.8337211609f,
4.8368387222f,
4.8435096741f,
5.1751475334f,
5.3748049736f,
6.1410837173f,
7.6529307365f,
7.5235214233f,
4.9108843803f,
4.8226222992f,
5.4057979584f,
5.4013924599f,
6.1410837173f,
6.3431472778f,
7.1083049774f,
7.6008300781f,
5.3137121201f,
5.6120514870f,
5.6066360474f,
6.0399808884f,
7.6529307365f,
7.1083049774f,
7.0943155289f,
7.0478363037f,
6.1676793098f,
6.3431472778f,
6.1075134277f,
6.7825231552f,
7.5235214233f,
7.6008300781f,
7.0478363037f,
6.9186143875f,
// c = 2
3.3038473129f,
10.0689258575f,
12.2785224915f,
14.6041173935f,
16.2107315063f,
19.2314529419f,
28.0129547119f,
55.6682891846f,
10.0689258575f,
11.4085016251f,
11.3871345520f,
15.4934167862f,
16.5364933014f,
14.9153423309f,
26.3748722076f,
40.8614425659f,
12.2785224915f,
11.3871345520f,
17.0886878967f,
13.9500350952f,
16.0003223419f,
28.5660629272f,
26.2124195099f,
30.1260128021f,
14.6041173935f,
15.4934167862f,
13.9500350952f,
21.1235027313f,
26.1579780579f,
25.5579223633f,
40.6859359741f,
33.8056335449f,
16.2107315063f,
16.5364933014f,
16.0003223419f,
26.1579780579f,
26.8042831421f,
26.1587715149f,
35.7343978882f,
43.6857032776f,
19.2314529419f,
14.9153423309f,
28.5660629272f,
25.5579223633f,
26.1587715149f,
34.5418128967f,
41.3197937012f,
48.7867660522f,
28.0129547119f,
26.3748722076f,
26.2124195099f,
40.6859359741f,
35.7343978882f,
41.3197937012f,
47.6329460144f,
55.3498458862f,
55.6682891846f,
40.8614425659f,
30.1260128021f,
33.8056335449f,
43.6857032776f,
48.7867660522f,
55.3498458862f,
63.6065597534f,
};
const float kBaseQuantMatrixYCbCr[] = {
// c = 0
1.2397409345866273f, //
1.7227115097630963f, //
2.9212167156636855f, //
2.812737435286529f, //
3.339819711906184f, //
3.463603762596166f, //
3.840915217993518f, //
3.86956f, //
1.7227115097630963f, //
2.0928894413636874f, //
2.8456760904429297f, //
2.704506820909662f, //
3.4407673520905337f, //
3.166232352090534f, //
4.025208741558432f, //
4.035324490952577f, //
2.9212167156636855f, //
2.8456760904429297f, //
2.9587403520905338f, //
3.3862948970669273f, //
3.619523781336757f, //
3.9046279999999998f, //
3.757835838431854f, //
4.237447515714274f, //
2.812737435286529f, //
2.704506820909662f, //
3.3862948970669273f, //
3.380058821812233f, //
4.1679867415584315f, //
4.805510627261856f, //
4.784259f, //
4.605934f, //
3.339819711906184f, //
3.4407673520905337f, //
3.619523781336757f, //
4.1679867415584315f, //
4.579851258441568f, //
4.923237f, //
5.574107f, //
5.48533336146308f, //
3.463603762596166f, //
3.166232352090534f, //
3.9046279999999998f, //
4.805510627261856f, //
4.923237f, //
5.43936f, //
5.093895741558431f, //
6.0872254423617225f, //
3.840915217993518f, //
4.025208741558432f, //
3.757835838431854f, //
4.784259f, //
5.574107f, //
5.093895741558431f, //
5.438461f, //
5.4037359493250845f, //
3.86956f, //
4.035324490952577f, //
4.237447515714274f, //
4.605934f, //
5.48533336146308f, //
6.0872254423617225f, //
5.4037359493250845f, //
4.37787101190424f,
// c = 1
2.8236197786377537f, //
6.495639358561486f, //
9.310489207538302f, //
10.64747864717083f, //
11.07419143098738f, //
17.146390223910462f, //
18.463982229408998f, //
29.087001644203088f, //
6.495639358561486f, //
8.890103846667353f, //
8.976895794294748f, //
13.666270550318826f, //
16.547071905624193f, //
16.63871382827686f, //
26.778396930893695f, //
21.33034294694781f, //
9.310489207538302f, //
8.976895794294748f, //
11.08737706005991f, //
18.20548239870446f, //
19.752481654011646f, //
23.985660533114896f, //
102.6457378402362f, //
24.450989f, //
10.64747864717083f, //
13.666270550318826f, //
18.20548239870446f, //
18.628012327860365f, //
16.042509519487183f, //
25.04918273242625f, //
25.017140189353015f, //
35.79788782635831f, //
11.07419143098738f, //
16.547071905624193f, //
19.752481654011646f, //
16.042509519487183f, //
19.373482748612577f, //
14.677529999999999f, //
19.94695960400931f, //
51.094112f, //
17.146390223910462f, //
16.63871382827686f, //
23.985660533114896f, //
25.04918273242625f, //
14.677529999999999f, //
31.320412426835304f, //
46.357234000000005f, //
67.48111451705412f, //
18.463982229408998f, //
26.778396930893695f, //
102.6457378402362f, //
25.017140189353015f, //
19.94695960400931f, //
46.357234000000005f, //
61.315764694388044f, //
88.34665293823721f, //
29.087001644203088f, //
21.33034294694781f, //
24.450989f, //
35.79788782635831f, //
51.094112f, //
67.48111451705412f, //
88.34665293823721f, //
112.16099098350989f,
// c = 2
2.9217254961255255f, //
4.497681013199305f, //
7.356344520940414f, //
6.583891506504051f, //
8.535608740100237f, //
8.799434353234647f, //
9.188341534163023f, //
9.482700481227672f, //
4.497681013199305f, //
6.309548851989123f, //
7.024608962670982f, //
7.156445324163424f, //
8.049059218663244f, //
7.0124290657218555f, //
6.711923184393611f, //
8.380307846134853f, //
7.356344520940414f, //
7.024608962670982f, //
6.892101177327445f, //
6.882819916277163f, //
8.782226090078568f, //
6.8774750000000004f, //
7.8858175969577955f, //
8.67909f, //
6.583891506504051f, //
7.156445324163424f, //
6.882819916277163f, //
7.003072944847055f, //
7.7223464701024875f, //
7.955425720217421f, //
7.4734110000000005f, //
8.362933242943903f, //
8.535608740100237f, //
8.049059218663244f, //
8.782226090078568f, //
7.7223464701024875f, //
6.778005927001542f, //
9.484922741558432f, //
9.043702663686046f, //
8.053178199770173f, //
8.799434353234647f, //
7.0124290657218555f, //
6.8774750000000004f, //
7.955425720217421f, //
9.484922741558432f, //
8.607606527385098f, //
9.922697394370815f, //
64.25135180237939f, //
9.188341534163023f, //
6.711923184393611f, //
7.8858175969577955f, //
7.4734110000000005f, //
9.043702663686046f, //
9.922697394370815f, //
63.184936549738225f, //
83.35294340273799f, //
9.482700481227672f, //
8.380307846134853f, //
8.67909f, //
8.362933242943903f, //
8.053178199770173f, //
64.25135180237939f, //
83.35294340273799f, //
114.89202448569779f, //
};
const float k420GlobalScale = 1.22;
const float k420Rescale[64] = {
0.4093, 0.3209, 0.3477, 0.3333, 0.3144, 0.2823, 0.3214, 0.3354, //
0.3209, 0.3111, 0.3489, 0.2801, 0.3059, 0.3119, 0.4135, 0.3445, //
0.3477, 0.3489, 0.3586, 0.3257, 0.2727, 0.3754, 0.3369, 0.3484, //
0.3333, 0.2801, 0.3257, 0.3020, 0.3515, 0.3410, 0.3971, 0.3839, //
0.3144, 0.3059, 0.2727, 0.3515, 0.3105, 0.3397, 0.2716, 0.3836, //
0.2823, 0.3119, 0.3754, 0.3410, 0.3397, 0.3212, 0.3203, 0.0726, //
0.3214, 0.4135, 0.3369, 0.3971, 0.2716, 0.3203, 0.0798, 0.0553, //
0.3354, 0.3445, 0.3484, 0.3839, 0.3836, 0.0726, 0.0553, 0.3368, //
};
const float kBaseQuantMatrixStd[] = {
// c = 0
16.0f, 11.0f, 10.0f, 16.0f, 24.0f, 40.0f, 51.0f, 61.0f, //
12.0f, 12.0f, 14.0f, 19.0f, 26.0f, 58.0f, 60.0f, 55.0f, //
14.0f, 13.0f, 16.0f, 24.0f, 40.0f, 57.0f, 69.0f, 56.0f, //
14.0f, 17.0f, 22.0f, 29.0f, 51.0f, 87.0f, 80.0f, 62.0f, //
18.0f, 22.0f, 37.0f, 56.0f, 68.0f, 109.0f, 103.0f, 77.0f, //
24.0f, 35.0f, 55.0f, 64.0f, 81.0f, 104.0f, 113.0f, 92.0f, //
49.0f, 64.0f, 78.0f, 87.0f, 103.0f, 121.0f, 120.0f, 101.0f, //
72.0f, 92.0f, 95.0f, 98.0f, 112.0f, 100.0f, 103.0f, 99.0f, //
// c = 1
17.0f, 18.0f, 24.0f, 47.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
18.0f, 21.0f, 26.0f, 66.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
24.0f, 26.0f, 56.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
47.0f, 66.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, 99.0f, //
};
const float kZeroBiasMulYCbCrLQ[] = {
// c = 0
0.0000f, 0.0568f, 0.3880f, 0.6190f, 0.6190f, 0.4490f, 0.4490f, 0.6187f, //
0.0568f, 0.5829f, 0.6189f, 0.6190f, 0.6190f, 0.7190f, 0.6190f, 0.6189f, //
0.3880f, 0.6189f, 0.6190f, 0.6190f, 0.6190f, 0.6190f, 0.6187f, 0.6100f, //
0.6190f, 0.6190f, 0.6190f, 0.6190f, 0.5890f, 0.3839f, 0.7160f, 0.6190f, //
0.6190f, 0.6190f, 0.6190f, 0.5890f, 0.6190f, 0.3880f, 0.5860f, 0.4790f, //
0.4490f, 0.7190f, 0.6190f, 0.3839f, 0.3880f, 0.6190f, 0.6190f, 0.6190f, //
0.4490f, 0.6190f, 0.6187f, 0.7160f, 0.5860f, 0.6190f, 0.6204f, 0.6190f, //
0.6187f, 0.6189f, 0.6100f, 0.6190f, 0.4790f, 0.6190f, 0.6190f, 0.3480f, //
// c = 1
0.0000f, 1.1640f, 0.9373f, 1.1319f, 0.8016f, 0.9136f, 1.1530f, 0.9430f, //
1.1640f, 0.9188f, 0.9160f, 1.1980f, 1.1830f, 0.9758f, 0.9430f, 0.9430f, //
0.9373f, 0.9160f, 0.8430f, 1.1720f, 0.7083f, 0.9430f, 0.9430f, 0.9430f, //
1.1319f, 1.1980f, 1.1720f, 1.1490f, 0.8547f, 0.9430f, 0.9430f, 0.9430f, //
0.8016f, 1.1830f, 0.7083f, 0.8547f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, //
0.9136f, 0.9758f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, //
1.1530f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9480f, //
0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9430f, 0.9480f, 0.9430f, //
// c = 2
0.0000f, 1.3190f, 0.4308f, 0.4460f, 0.0661f, 0.0660f, 0.2660f, 0.2960f, //
1.3190f, 0.3280f, 0.3093f, 0.0750f, 0.0505f, 0.1594f, 0.3060f, 0.2113f, //
0.4308f, 0.3093f, 0.3060f, 0.1182f, 0.0500f, 0.3060f, 0.3915f, 0.2426f, //
0.4460f, 0.0750f, 0.1182f, 0.0512f, 0.0500f, 0.2130f, 0.3930f, 0.1590f, //
0.0661f, 0.0505f, 0.0500f, 0.0500f, 0.3055f, 0.3360f, 0.5148f, 0.5403f, //
0.0660f, 0.1594f, 0.3060f, 0.2130f, 0.3360f, 0.5060f, 0.5874f, 0.3060f, //
0.2660f, 0.3060f, 0.3915f, 0.3930f, 0.5148f, 0.5874f, 0.3060f, 0.3060f, //
0.2960f, 0.2113f, 0.2426f, 0.1590f, 0.5403f, 0.3060f, 0.3060f, 0.3060f, //
};
const float kZeroBiasMulYCbCrHQ[] = {
// c = 0
0.0000f, 0.0044f, 0.2521f, 0.6547f, 0.8161f, 0.6130f, 0.8841f, 0.8155f, //
0.0044f, 0.6831f, 0.6553f, 0.6295f, 0.7848f, 0.7843f, 0.8474f, 0.7836f, //
0.2521f, 0.6553f, 0.7834f, 0.7829f, 0.8161f, 0.8072f, 0.7743f, 0.9242f, //
0.6547f, 0.6295f, 0.7829f, 0.8654f, 0.7829f, 0.6986f, 0.7818f, 0.7726f, //
0.8161f, 0.7848f, 0.8161f, 0.7829f, 0.7471f, 0.7827f, 0.7843f, 0.7653f, //
0.6130f, 0.7843f, 0.8072f, 0.6986f, 0.7827f, 0.7848f, 0.9508f, 0.7653f, //
0.8841f, 0.8474f, 0.7743f, 0.7818f, 0.7843f, 0.9508f, 0.7839f, 0.8437f, //
0.8155f, 0.7836f, 0.9242f, 0.7726f, 0.7653f, 0.7653f, 0.8437f, 0.7819f, //
// c = 1
0.0000f, 1.0816f, 1.0556f, 1.2876f, 1.1554f, 1.1567f, 1.8851f, 0.5488f, //
1.0816f, 1.1537f, 1.1850f, 1.0712f, 1.1671f, 2.0719f, 1.0544f, 1.4764f, //
1.0556f, 1.1850f, 1.2870f, 1.1981f, 1.8181f, 1.2618f, 1.0564f, 1.1191f, //
1.2876f, 1.0712f, 1.1981f, 1.4753f, 2.0609f, 1.0564f, 1.2645f, 1.0564f, //
1.1554f, 1.1671f, 1.8181f, 2.0609f, 0.7324f, 1.1163f, 0.8464f, 1.0564f, //
1.1567f, 2.0719f, 1.2618f, 1.0564f, 1.1163f, 1.0040f, 1.0564f, 1.0564f, //
1.8851f, 1.0544f, 1.0564f, 1.2645f, 0.8464f, 1.0564f, 1.0564f, 1.0564f, //
0.5488f, 1.4764f, 1.1191f, 1.0564f, 1.0564f, 1.0564f, 1.0564f, 1.0564f, //
// c = 2
0.0000f, 0.5392f, 0.6659f, 0.8968f, 0.6829f, 0.6328f, 0.5802f, 0.4836f, //
0.5392f, 0.6746f, 0.6760f, 0.6102f, 0.6015f, 0.6958f, 0.7327f, 0.4897f, //
0.6659f, 0.6760f, 0.6957f, 0.6543f, 0.4396f, 0.6330f, 0.7081f, 0.2583f, //
0.8968f, 0.6102f, 0.6543f, 0.5913f, 0.6457f, 0.5828f, 0.5139f, 0.3565f, //
0.6829f, 0.6015f, 0.4396f, 0.6457f, 0.5633f, 0.4263f, 0.6371f, 0.5949f, //
0.6328f, 0.6958f, 0.6330f, 0.5828f, 0.4263f, 0.2847f, 0.2909f, 0.6629f, //
0.5802f, 0.7327f, 0.7081f, 0.5139f, 0.6371f, 0.2909f, 0.6644f, 0.6644f, //
0.4836f, 0.4897f, 0.2583f, 0.3565f, 0.5949f, 0.6629f, 0.6644f, 0.6644f, //
};
const float kZeroBiasOffsetYCbCrDC[] = {0.0f, 0.0f, 0.0f};
const float kZeroBiasOffsetYCbCrAC[] = {
0.59082f,
0.58146f,
0.57988f,
};
constexpr uint8_t kTransferFunctionPQ = 16;
constexpr uint8_t kTransferFunctionHLG = 18;
float DistanceToLinearQuality(float distance) {
if (distance <= 0.1f) {
return 1.0f;
} else if (distance <= 4.6f) {
return (200.0f / 9.0f) * (distance - 0.1f);
} else if (distance <= 6.4f) {
return 5000.0f / (100.0f - (distance - 0.1f) / 0.09f);
} else if (distance < 25.0f) {
return 530000.0f /
(3450.0f -
300.0f * std::sqrt((848.0f * distance - 5330.0f) / 120.0f));
} else {
return 5000.0f;
}
}
constexpr float kExponent[DCTSIZE2] = {
1.00f, 0.51f, 0.67f, 0.74f, 1.00f, 1.00f, 1.00f, 1.00f, //
0.51f, 0.66f, 0.69f, 0.87f, 1.00f, 1.00f, 1.00f, 1.00f, //
0.67f, 0.69f, 0.84f, 0.83f, 0.96f, 1.00f, 1.00f, 1.00f, //
0.74f, 0.87f, 0.83f, 1.00f, 1.00f, 0.91f, 0.91f, 1.00f, //
1.00f, 1.00f, 0.96f, 1.00f, 1.00f, 1.00f, 1.00f, 1.00f, //
1.00f, 1.00f, 1.00f, 0.91f, 1.00f, 1.00f, 1.00f, 1.00f, //
1.00f, 1.00f, 1.00f, 0.91f, 1.00f, 1.00f, 1.00f, 1.00f, //
1.00f, 1.00f, 1.00f, 1.00f, 1.00f, 1.00f, 1.00f, 1.00f, //
};
constexpr float kDist0 = 1.5f; // distance where non-linearity kicks in.
float DistanceToScale(float distance, int k) {
if (distance < kDist0) {
return distance;
}
const float exp = kExponent[k];
const float mul = std::pow(kDist0, 1.0 - exp);
return std::max<float>(0.5f * distance, mul * std::pow(distance, exp));
}
float ScaleToDistance(float scale, int k) {
if (scale < kDist0) {
return scale;
}
const float exp = 1.0 / kExponent[k];
const float mul = std::pow(kDist0, 1.0 - exp);
return std::min<float>(2.0f * scale, mul * std::pow(scale, exp));
}
float QuantValsToDistance(j_compress_ptr cinfo) {
jpeg_comp_master* m = cinfo->master;
float global_scale = kGlobalScaleYCbCr;
if (m->cicp_transfer_function == kTransferFunctionPQ) {
global_scale *= .4f;
} else if (m->cicp_transfer_function == kTransferFunctionHLG) {
global_scale *= .5f;
}
int quant_max = m->force_baseline ? 255 : 32767U;
static const float kDistMax = 10000.0f;
float dist_min = 0.0f;
float dist_max = kDistMax;
for (int c = 0; c < cinfo->num_components; ++c) {
int quant_idx = cinfo->comp_info[c].quant_tbl_no;
uint16_t* quantval = cinfo->quant_tbl_ptrs[quant_idx]->quantval;
const float* base_qm = &kBaseQuantMatrixYCbCr[quant_idx * DCTSIZE2];
for (int k = 0; k < DCTSIZE2; ++k) {
float dmin = 0.0;
float dmax = kDistMax;
float invq = 1.0f / base_qm[k] / global_scale;
int qval = quantval[k];
if (qval > 1) {
float scale_min = (qval - 0.5f) * invq;
dmin = ScaleToDistance(scale_min, k);
}
if (qval < quant_max) {
float scale_max = (qval + 0.5f) * invq;
dmax = ScaleToDistance(scale_max, k);
}
if (dmin <= dist_max) {
dist_min = std::max(dmin, dist_min);
}
if (dmax >= dist_min) {
dist_max = std::min(dist_max, dmax);
}
}
}
float distance;
if (dist_min == 0) {
distance = dist_max;
} else if (dist_max == kDistMax) {
distance = dist_min;
} else {
distance = 0.5f * (dist_min + dist_max);
}
return distance;
}
bool IsYUV420(j_compress_ptr cinfo) {
return (cinfo->jpeg_color_space == JCS_YCbCr &&
cinfo->comp_info[0].h_samp_factor == 2 &&
cinfo->comp_info[0].v_samp_factor == 2 &&
cinfo->comp_info[1].h_samp_factor == 1 &&
cinfo->comp_info[1].v_samp_factor == 1 &&
cinfo->comp_info[2].h_samp_factor == 1 &&
cinfo->comp_info[2].v_samp_factor == 1);
}
} // namespace
void SetQuantMatrices(j_compress_ptr cinfo, float distances[NUM_QUANT_TBLS],
bool add_two_chroma_tables) {
jpeg_comp_master* m = cinfo->master;
const bool xyb = m->xyb_mode && cinfo->jpeg_color_space == JCS_RGB;
const bool is_yuv420 = IsYUV420(cinfo);
float global_scale;
bool non_linear_scaling = true;
const float* base_quant_matrix[NUM_QUANT_TBLS];
int num_base_tables;
if (xyb) {
global_scale = kGlobalScaleXYB;
num_base_tables = 3;
base_quant_matrix[0] = kBaseQuantMatrixXYB;
base_quant_matrix[1] = kBaseQuantMatrixXYB + DCTSIZE2;
base_quant_matrix[2] = kBaseQuantMatrixXYB + 2 * DCTSIZE2;
} else if (cinfo->jpeg_color_space == JCS_YCbCr && !m->use_std_tables) {
global_scale = kGlobalScaleYCbCr;
if (m->cicp_transfer_function == kTransferFunctionPQ) {
global_scale *= .4f;
} else if (m->cicp_transfer_function == kTransferFunctionHLG) {
global_scale *= .5f;
}
if (is_yuv420) {
global_scale *= k420GlobalScale;
}
if (add_two_chroma_tables) {
cinfo->comp_info[2].quant_tbl_no = 2;
num_base_tables = 3;
base_quant_matrix[0] = kBaseQuantMatrixYCbCr;
base_quant_matrix[1] = kBaseQuantMatrixYCbCr + DCTSIZE2;
base_quant_matrix[2] = kBaseQuantMatrixYCbCr + 2 * DCTSIZE2;
} else {
num_base_tables = 2;
base_quant_matrix[0] = kBaseQuantMatrixYCbCr;
// Use the Cr table for both Cb and Cr.
base_quant_matrix[1] = kBaseQuantMatrixYCbCr + 2 * DCTSIZE2;
}
} else {
global_scale = 0.01f;
non_linear_scaling = false;
num_base_tables = 2;
base_quant_matrix[0] = kBaseQuantMatrixStd;
base_quant_matrix[1] = kBaseQuantMatrixStd + DCTSIZE2;
}
int quant_max = m->force_baseline ? 255 : 32767U;
for (int quant_idx = 0; quant_idx < num_base_tables; ++quant_idx) {
const float* base_qm = base_quant_matrix[quant_idx];
JQUANT_TBL** qtable = &cinfo->quant_tbl_ptrs[quant_idx];
if (*qtable == nullptr) {
*qtable = jpegli_alloc_quant_table(reinterpret_cast<j_common_ptr>(cinfo));
}
for (int k = 0; k < DCTSIZE2; ++k) {
float scale = global_scale;
if (non_linear_scaling) {
scale *= DistanceToScale(distances[quant_idx], k);
if (is_yuv420 && quant_idx > 0) {
scale *= k420Rescale[k];
}
} else {
scale *= DistanceToLinearQuality(distances[quant_idx]);
}
int qval = std::round(scale * base_qm[k]);
(*qtable)->quantval[k] = std::max(1, std::min(qval, quant_max));
}
(*qtable)->sent_table = FALSE;
}
}
void InitQuantizer(j_compress_ptr cinfo, QuantPass pass) {
jpeg_comp_master* m = cinfo->master;
// Compute quantization multupliers from the quant table values.
for (int c = 0; c < cinfo->num_components; ++c) {
int quant_idx = cinfo->comp_info[c].quant_tbl_no;
JQUANT_TBL* quant_table = cinfo->quant_tbl_ptrs[quant_idx];
if (!quant_table) {
JPEGLI_ERROR("Missing quantization table %d for component %d", quant_idx,
c);
}
for (size_t k = 0; k < DCTSIZE2; k++) {
int val = quant_table->quantval[k];
if (val == 0) {
JPEGLI_ERROR("Invalid quantval 0.");
}
switch (pass) {
case QuantPass::NO_SEARCH:
m->quant_mul[c][k] = 8.0f / val;
break;
case QuantPass::SEARCH_FIRST_PASS:
m->quant_mul[c][k] = 128.0f;
break;
case QuantPass::SEARCH_SECOND_PASS:
m->quant_mul[c][kJPEGZigZagOrder[k]] = 1.0f / (16 * val);
break;
}
}
}
if (m->use_adaptive_quantization) {
for (int c = 0; c < cinfo->num_components; ++c) {
for (int k = 0; k < DCTSIZE2; ++k) {
m->zero_bias_mul[c][k] = k == 0 ? 0.0f : 0.5f;
m->zero_bias_offset[c][k] = k == 0 ? 0.0f : 0.5f;
}
}
if (cinfo->jpeg_color_space == JCS_YCbCr) {
float distance = QuantValsToDistance(cinfo);
static const float kDistHQ = 1.0f;
static const float kDistLQ = 3.0f;
float mix0 = (distance - kDistHQ) / (kDistLQ - kDistHQ);
mix0 = std::max(0.0f, std::min(1.0f, mix0));
float mix1 = 1.0f - mix0;
for (int c = 0; c < cinfo->num_components; ++c) {
for (int k = 0; k < DCTSIZE2; ++k) {
float mul0 = kZeroBiasMulYCbCrLQ[c * DCTSIZE2 + k];
float mul1 = kZeroBiasMulYCbCrHQ[c * DCTSIZE2 + k];
m->zero_bias_mul[c][k] = mix0 * mul0 + mix1 * mul1;
m->zero_bias_offset[c][k] =
k == 0 ? kZeroBiasOffsetYCbCrDC[c] : kZeroBiasOffsetYCbCrAC[c];
}
}
}
} else if (cinfo->jpeg_color_space == JCS_YCbCr) {
for (int c = 0; c < cinfo->num_components; ++c) {
for (int k = 0; k < DCTSIZE2; ++k) {
m->zero_bias_offset[c][k] =
k == 0 ? kZeroBiasOffsetYCbCrDC[c] : kZeroBiasOffsetYCbCrAC[c];
}
}
}
}
} // namespace jpegli