// 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 #include #include #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(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(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(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