tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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image_metadata.cc (20547B)


      1 // Copyright (c) the JPEG XL Project Authors. All rights reserved.
      2 //
      3 // Use of this source code is governed by a BSD-style
      4 // license that can be found in the LICENSE file.
      5 
      6 #include "lib/jxl/image_metadata.h"
      7 
      8 #include <limits>
      9 #include <utility>
     10 
     11 #include "lib/jxl/alpha.h"
     12 #include "lib/jxl/base/byte_order.h"
     13 #include "lib/jxl/base/matrix_ops.h"
     14 #include "lib/jxl/cms/opsin_params.h"
     15 #include "lib/jxl/fields.h"
     16 #include "lib/jxl/frame_header.h"
     17 #include "lib/jxl/quantizer.h"
     18 
     19 namespace jxl {
     20 BitDepth::BitDepth() { Bundle::Init(this); }
     21 Status BitDepth::VisitFields(Visitor* JXL_RESTRICT visitor) {
     22  JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &floating_point_sample));
     23  // The same fields (bits_per_sample and exponent_bits_per_sample) are read
     24  // in a different way depending on floating_point_sample's value. It's still
     25  // default-initialized correctly so using visitor->Conditional is not
     26  // required.
     27  if (!floating_point_sample) {
     28    JXL_QUIET_RETURN_IF_ERROR(visitor->U32(
     29        Val(8), Val(10), Val(12), BitsOffset(6, 1), 8, &bits_per_sample));
     30    exponent_bits_per_sample = 0;
     31  } else {
     32    JXL_QUIET_RETURN_IF_ERROR(visitor->U32(
     33        Val(32), Val(16), Val(24), BitsOffset(6, 1), 32, &bits_per_sample));
     34    // The encoded value is exponent_bits_per_sample - 1, encoded in 3 bits
     35    // so the value can be in range [1, 8].
     36    const uint32_t offset = 1;
     37    exponent_bits_per_sample -= offset;
     38    JXL_QUIET_RETURN_IF_ERROR(
     39        visitor->Bits(4, 8 - offset, &exponent_bits_per_sample));
     40    exponent_bits_per_sample += offset;
     41  }
     42 
     43  // Error-checking for floating point ranges.
     44  if (floating_point_sample) {
     45    if (exponent_bits_per_sample < 2 || exponent_bits_per_sample > 8) {
     46      return JXL_FAILURE("Invalid exponent_bits_per_sample: %u",
     47                         exponent_bits_per_sample);
     48    }
     49    int mantissa_bits =
     50        static_cast<int>(bits_per_sample) - exponent_bits_per_sample - 1;
     51    if (mantissa_bits < 2 || mantissa_bits > 23) {
     52      return JXL_FAILURE("Invalid bits_per_sample: %u", bits_per_sample);
     53    }
     54  } else {
     55    if (bits_per_sample > 31) {
     56      return JXL_FAILURE("Invalid bits_per_sample: %u", bits_per_sample);
     57    }
     58  }
     59  return true;
     60 }
     61 
     62 #if JXL_DEBUG_V_LEVEL >= 1
     63 std::string BitDepth::DebugString() const {
     64  std::ostringstream os;
     65  os << (floating_point_sample ? "F" : "U");
     66  os << bits_per_sample;
     67  if (floating_point_sample) os << "." << exponent_bits_per_sample;
     68  return os.str();
     69 }
     70 #endif
     71 
     72 CustomTransformData::CustomTransformData() { Bundle::Init(this); }
     73 Status CustomTransformData::VisitFields(Visitor* JXL_RESTRICT visitor) {
     74  if (visitor->AllDefault(*this, &all_default)) {
     75    // Overwrite all serialized fields, but not any nonserialized_*.
     76    visitor->SetDefault(this);
     77    return true;
     78  }
     79  if (visitor->Conditional(nonserialized_xyb_encoded)) {
     80    JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&opsin_inverse_matrix));
     81  }
     82  JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(3, 0, &custom_weights_mask));
     83  if (visitor->Conditional((custom_weights_mask & 0x1) != 0)) {
     84    // 4 5x5 kernels, but all of them can be obtained by symmetry from one,
     85    // which is symmetric along its main diagonal. The top-left kernel is
     86    // defined by
     87    //
     88    // 0  1  2  3  4
     89    // 1  5  6  7  8
     90    // 2  6  9 10 11
     91    // 3  7 10 12 13
     92    // 4  8 11 13 14
     93    float constexpr kWeights2[15] = {
     94        -0.01716200f, -0.03452303f, -0.04022174f, -0.02921014f, -0.00624645f,
     95        0.14111091f,  0.28896755f,  0.00278718f,  -0.01610267f, 0.56661550f,
     96        0.03777607f,  -0.01986694f, -0.03144731f, -0.01185068f, -0.00213539f};
     97    for (size_t i = 0; i < 15; i++) {
     98      JXL_QUIET_RETURN_IF_ERROR(
     99          visitor->F16(kWeights2[i], &upsampling2_weights[i]));
    100    }
    101  }
    102  if (visitor->Conditional((custom_weights_mask & 0x2) != 0)) {
    103    // 16 5x5 kernels, but all of them can be obtained by symmetry from
    104    // three, two of which are symmetric along their main diagonals. The top
    105    // left 4 kernels are defined by
    106    //
    107    // 0  1  2  3  4   5  6  7  8  9
    108    // 1 10 11 12 13  14 15 16 17 18
    109    // 2 11 19 20 21  22 23 24 25 26
    110    // 3 12 20 27 28  29 30 31 32 33
    111    // 4 13 21 28 34  35 36 37 38 39
    112    //
    113    // 5 14 22 29 35  40 41 42 43 44
    114    // 6 15 23 30 36  41 45 46 47 48
    115    // 7 16 24 31 37  42 46 49 50 51
    116    // 8 17 25 32 38  43 47 50 52 53
    117    // 9 18 26 33 39  44 48 51 53 54
    118    constexpr float kWeights4[55] = {
    119        -0.02419067f, -0.03491987f, -0.03693351f, -0.03094285f, -0.00529785f,
    120        -0.01663432f, -0.03556863f, -0.03888905f, -0.03516850f, -0.00989469f,
    121        0.23651958f,  0.33392945f,  -0.01073543f, -0.01313181f, -0.03556694f,
    122        0.13048175f,  0.40103025f,  0.03951150f,  -0.02077584f, 0.46914198f,
    123        -0.00209270f, -0.01484589f, -0.04064806f, 0.18942530f,  0.56279892f,
    124        0.06674400f,  -0.02335494f, -0.03551682f, -0.00754830f, -0.02267919f,
    125        -0.02363578f, 0.00315804f,  -0.03399098f, -0.01359519f, -0.00091653f,
    126        -0.00335467f, -0.01163294f, -0.01610294f, -0.00974088f, -0.00191622f,
    127        -0.01095446f, -0.03198464f, -0.04455121f, -0.02799790f, -0.00645912f,
    128        0.06390599f,  0.22963888f,  0.00630981f,  -0.01897349f, 0.67537268f,
    129        0.08483369f,  -0.02534994f, -0.02205197f, -0.01667999f, -0.00384443f};
    130    for (size_t i = 0; i < 55; i++) {
    131      JXL_QUIET_RETURN_IF_ERROR(
    132          visitor->F16(kWeights4[i], &upsampling4_weights[i]));
    133    }
    134  }
    135  if (visitor->Conditional((custom_weights_mask & 0x4) != 0)) {
    136    // typo:off
    137    // 64 5x5 kernels, all of them can be obtained by symmetry from
    138    // 10, 4 of which are symmetric along their main diagonals. The top
    139    // left 16 kernels are defined by
    140    //  0  1  2  3  4   5  6  7  8  9   a  b  c  d  e   f 10 11 12 13
    141    //  1 14 15 16 17  18 19 1a 1b 1c  1d 1e 1f 20 21  22 23 24 25 26
    142    //  2 15 27 28 29  2a 2b 2c 2d 2e  2f 30 31 32 33  34 35 36 37 38
    143    //  3 16 28 39 3a  3b 3c 3d 3e 3f  40 41 42 43 44  45 46 47 48 49
    144    //  4 17 29 3a 4a  4b 4c 4d 4e 4f  50 51 52 53 54  55 56 57 58 59
    145 
    146    //  5 18 2a 3b 4b  5a 5b 5c 5d 5e  5f 60 61 62 63  64 65 66 67 68
    147    //  6 19 2b 3c 4c  5b 69 6a 6b 6c  6d 6e 6f 70 71  72 73 74 75 76
    148    //  7 1a 2c 3d 4d  5c 6a 77 78 79  7a 7b 7c 7d 7e  7f 80 81 82 83
    149    //  8 1b 2d 3e 4e  5d 6b 78 84 85  86 87 88 89 8a  8b 8c 8d 8e 8f
    150    //  9 1c 2e 3f 4f  5e 6c 79 85 90  91 92 93 94 95  96 97 98 99 9a
    151 
    152    //  a 1d 2f 40 50  5f 6d 7a 86 91  9b 9c 9d 9e 9f  a0 a1 a2 a3 a4
    153    //  b 1e 30 41 51  60 6e 7b 87 92  9c a5 a6 a7 a8  a9 aa ab ac ad
    154    //  c 1f 31 42 52  61 6f 7c 88 93  9d a6 ae af b0  b1 b2 b3 b4 b5
    155    //  d 20 32 43 53  62 70 7d 89 94  9e a7 af b6 b7  b8 b9 ba bb bc
    156    //  e 21 33 44 54  63 71 7e 8a 95  9f a8 b0 b7 bd  be bf c0 c1 c2
    157 
    158    //  f 22 34 45 55  64 72 7f 8b 96  a0 a9 b1 b8 be  c3 c4 c5 c6 c7
    159    // 10 23 35 46 56  65 73 80 8c 97  a1 aa b2 b9 bf  c4 c8 c9 ca cb
    160    // 11 24 36 47 57  66 74 81 8d 98  a2 ab b3 ba c0  c5 c9 cc cd ce
    161    // 12 25 37 48 58  67 75 82 8e 99  a3 ac b4 bb c1  c6 ca cd cf d0
    162    // 13 26 38 49 59  68 76 83 8f 9a  a4 ad b5 bc c2  c7 cb ce d0 d1
    163    // typo:on
    164    constexpr float kWeights8[210] = {
    165        -0.02928613f, -0.03706353f, -0.03783812f, -0.03324558f, -0.00447632f,
    166        -0.02519406f, -0.03752601f, -0.03901508f, -0.03663285f, -0.00646649f,
    167        -0.02066407f, -0.03838633f, -0.04002101f, -0.03900035f, -0.00901973f,
    168        -0.01626393f, -0.03954148f, -0.04046620f, -0.03979621f, -0.01224485f,
    169        0.29895328f,  0.35757708f,  -0.02447552f, -0.01081748f, -0.04314594f,
    170        0.23903219f,  0.41119301f,  -0.00573046f, -0.01450239f, -0.04246845f,
    171        0.17567618f,  0.45220643f,  0.02287757f,  -0.01936783f, -0.03583255f,
    172        0.11572472f,  0.47416733f,  0.06284440f,  -0.02685066f, 0.42720050f,
    173        -0.02248939f, -0.01155273f, -0.04562755f, 0.28689496f,  0.49093869f,
    174        -0.00007891f, -0.01545926f, -0.04562659f, 0.21238920f,  0.53980934f,
    175        0.03369474f,  -0.02070211f, -0.03866988f, 0.14229550f,  0.56593398f,
    176        0.08045181f,  -0.02888298f, -0.03680918f, -0.00542229f, -0.02920477f,
    177        -0.02788574f, -0.02118180f, -0.03942402f, -0.00775547f, -0.02433614f,
    178        -0.03193943f, -0.02030828f, -0.04044014f, -0.01074016f, -0.01930822f,
    179        -0.03620399f, -0.01974125f, -0.03919545f, -0.01456093f, -0.00045072f,
    180        -0.00360110f, -0.01020207f, -0.01231907f, -0.00638988f, -0.00071592f,
    181        -0.00279122f, -0.00957115f, -0.01288327f, -0.00730937f, -0.00107783f,
    182        -0.00210156f, -0.00890705f, -0.01317668f, -0.00813895f, -0.00153491f,
    183        -0.02128481f, -0.04173044f, -0.04831487f, -0.03293190f, -0.00525260f,
    184        -0.01720322f, -0.04052736f, -0.05045706f, -0.03607317f, -0.00738030f,
    185        -0.01341764f, -0.03965629f, -0.05151616f, -0.03814886f, -0.01005819f,
    186        0.18968273f,  0.33063684f,  -0.01300105f, -0.01372950f, -0.04017465f,
    187        0.13727832f,  0.36402234f,  0.01027890f,  -0.01832107f, -0.03365072f,
    188        0.08734506f,  0.38194295f,  0.04338228f,  -0.02525993f, 0.56408126f,
    189        0.00458352f,  -0.01648227f, -0.04887868f, 0.24585519f,  0.62026135f,
    190        0.04314807f,  -0.02213737f, -0.04158014f, 0.16637289f,  0.65027023f,
    191        0.09621636f,  -0.03101388f, -0.04082742f, -0.00904519f, -0.02790922f,
    192        -0.02117818f, 0.00798662f,  -0.03995711f, -0.01243427f, -0.02231705f,
    193        -0.02946266f, 0.00992055f,  -0.03600283f, -0.01684920f, -0.00111684f,
    194        -0.00411204f, -0.01297130f, -0.01723725f, -0.01022545f, -0.00165306f,
    195        -0.00313110f, -0.01218016f, -0.01763266f, -0.01125620f, -0.00231663f,
    196        -0.01374149f, -0.03797620f, -0.05142937f, -0.03117307f, -0.00581914f,
    197        -0.01064003f, -0.03608089f, -0.05272168f, -0.03375670f, -0.00795586f,
    198        0.09628104f,  0.27129991f,  -0.00353779f, -0.01734151f, -0.03153981f,
    199        0.05686230f,  0.28500998f,  0.02230594f,  -0.02374955f, 0.68214326f,
    200        0.05018048f,  -0.02320852f, -0.04383616f, 0.18459474f,  0.71517975f,
    201        0.10805613f,  -0.03263677f, -0.03637639f, -0.01394373f, -0.02511203f,
    202        -0.01728636f, 0.05407331f,  -0.02867568f, -0.01893131f, -0.00240854f,
    203        -0.00446511f, -0.01636187f, -0.02377053f, -0.01522848f, -0.00333334f,
    204        -0.00819975f, -0.02964169f, -0.04499287f, -0.02745350f, -0.00612408f,
    205        0.02727416f,  0.19446600f,  0.00159832f,  -0.02232473f, 0.74982506f,
    206        0.11452620f,  -0.03348048f, -0.01605681f, -0.02070339f, -0.00458223f};
    207    for (size_t i = 0; i < 210; i++) {
    208      JXL_QUIET_RETURN_IF_ERROR(
    209          visitor->F16(kWeights8[i], &upsampling8_weights[i]));
    210    }
    211  }
    212  return true;
    213 }
    214 
    215 ExtraChannelInfo::ExtraChannelInfo() { Bundle::Init(this); }
    216 Status ExtraChannelInfo::VisitFields(Visitor* JXL_RESTRICT visitor) {
    217  if (visitor->AllDefault(*this, &all_default)) {
    218    // Overwrite all serialized fields, but not any nonserialized_*.
    219    visitor->SetDefault(this);
    220    return true;
    221  }
    222 
    223  // General
    224  JXL_QUIET_RETURN_IF_ERROR(visitor->Enum(ExtraChannel::kAlpha, &type));
    225 
    226  JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&bit_depth));
    227 
    228  JXL_QUIET_RETURN_IF_ERROR(
    229      visitor->U32(Val(0), Val(3), Val(4), BitsOffset(3, 1), 0, &dim_shift));
    230  if ((1U << dim_shift) > 8) {
    231    return JXL_FAILURE("dim_shift %u too large", dim_shift);
    232  }
    233 
    234  JXL_QUIET_RETURN_IF_ERROR(VisitNameString(visitor, &name));
    235 
    236  // Conditional
    237  if (visitor->Conditional(type == ExtraChannel::kAlpha)) {
    238    JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &alpha_associated));
    239  }
    240  if (visitor->Conditional(type == ExtraChannel::kSpotColor)) {
    241    for (float& c : spot_color) {
    242      JXL_QUIET_RETURN_IF_ERROR(visitor->F16(0, &c));
    243    }
    244  }
    245  if (visitor->Conditional(type == ExtraChannel::kCFA)) {
    246    JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(1), Bits(2), BitsOffset(4, 3),
    247                                           BitsOffset(8, 19), 1, &cfa_channel));
    248  }
    249 
    250  if (type == ExtraChannel::kUnknown ||
    251      (static_cast<int>(ExtraChannel::kReserved0) <= static_cast<int>(type) &&
    252       static_cast<int>(type) <= static_cast<int>(ExtraChannel::kReserved7))) {
    253    return JXL_FAILURE("Unknown extra channel (bits %u, shift %u, name '%s')\n",
    254                       bit_depth.bits_per_sample, dim_shift, name.c_str());
    255  }
    256  return true;
    257 }
    258 
    259 #if JXL_DEBUG_V_LEVEL >= 1
    260 std::string ExtraChannelInfo::DebugString() const {
    261  std::ostringstream os;
    262  os << (type == ExtraChannel::kAlpha           ? "Alpha"
    263         : type == ExtraChannel::kDepth         ? "Depth"
    264         : type == ExtraChannel::kSpotColor     ? "Spot"
    265         : type == ExtraChannel::kSelectionMask ? "Mask"
    266         : type == ExtraChannel::kBlack         ? "Black"
    267         : type == ExtraChannel::kCFA           ? "CFA"
    268         : type == ExtraChannel::kThermal       ? "Thermal"
    269                                                : "Unknown");
    270  if (type == ExtraChannel::kAlpha && alpha_associated) os << "(premul)";
    271  os << " " << bit_depth.DebugString();
    272  os << " shift: " << dim_shift;
    273  return os.str();
    274 }
    275 #endif
    276 
    277 ImageMetadata::ImageMetadata() { Bundle::Init(this); }
    278 Status ImageMetadata::VisitFields(Visitor* JXL_RESTRICT visitor) {
    279  if (visitor->AllDefault(*this, &all_default)) {
    280    // Overwrite all serialized fields, but not any nonserialized_*.
    281    visitor->SetDefault(this);
    282    return true;
    283  }
    284 
    285  // Bundle::AllDefault does not allow usage when reading (it may abort the
    286  // program when a codestream has invalid values), but when reading we
    287  // overwrite the extra_fields value, so do not need to call AllDefault.
    288  bool tone_mapping_default =
    289      visitor->IsReading() ? false : Bundle::AllDefault(tone_mapping);
    290 
    291  bool extra_fields = (orientation != 1 || have_preview || have_animation ||
    292                       have_intrinsic_size || !tone_mapping_default);
    293  JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &extra_fields));
    294  if (visitor->Conditional(extra_fields)) {
    295    orientation--;
    296    JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(3, 0, &orientation));
    297    orientation++;
    298    // (No need for bounds checking because we read exactly 3 bits)
    299 
    300    JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &have_intrinsic_size));
    301    if (visitor->Conditional(have_intrinsic_size)) {
    302      JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&intrinsic_size));
    303    }
    304    JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &have_preview));
    305    if (visitor->Conditional(have_preview)) {
    306      JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&preview_size));
    307    }
    308    JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &have_animation));
    309    if (visitor->Conditional(have_animation)) {
    310      JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&animation));
    311    }
    312  } else {
    313    orientation = 1;  // identity
    314    have_intrinsic_size = false;
    315    have_preview = false;
    316    have_animation = false;
    317  }
    318 
    319  JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&bit_depth));
    320  JXL_QUIET_RETURN_IF_ERROR(
    321      visitor->Bool(true, &modular_16_bit_buffer_sufficient));
    322 
    323  num_extra_channels = extra_channel_info.size();
    324  JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(0), Val(1), BitsOffset(4, 2),
    325                                         BitsOffset(12, 1), 0,
    326                                         &num_extra_channels));
    327 
    328  if (visitor->Conditional(num_extra_channels != 0)) {
    329    if (visitor->IsReading()) {
    330      extra_channel_info.resize(num_extra_channels);
    331    }
    332    for (ExtraChannelInfo& eci : extra_channel_info) {
    333      JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&eci));
    334    }
    335  }
    336 
    337  JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(true, &xyb_encoded));
    338  JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&color_encoding));
    339  if (visitor->Conditional(extra_fields)) {
    340    JXL_QUIET_RETURN_IF_ERROR(visitor->VisitNested(&tone_mapping));
    341  }
    342 
    343  // Treat as if only the fields up to extra channels exist.
    344  if (visitor->IsReading() && nonserialized_only_parse_basic_info) {
    345    return true;
    346  }
    347 
    348  JXL_QUIET_RETURN_IF_ERROR(visitor->BeginExtensions(&extensions));
    349  // Extensions: in chronological order of being added to the format.
    350  return visitor->EndExtensions();
    351 }
    352 
    353 OpsinInverseMatrix::OpsinInverseMatrix() { Bundle::Init(this); }
    354 Status OpsinInverseMatrix::VisitFields(Visitor* JXL_RESTRICT visitor) {
    355  if (visitor->AllDefault(*this, &all_default)) {
    356    // Overwrite all serialized fields, but not any nonserialized_*.
    357    visitor->SetDefault(this);
    358    return true;
    359  }
    360  const Matrix3x3& default_inverse =
    361      jxl::cms::DefaultInverseOpsinAbsorbanceMatrix();
    362  for (int j = 0; j < 3; ++j) {
    363    for (int i = 0; i < 3; ++i) {
    364      JXL_QUIET_RETURN_IF_ERROR(
    365          visitor->F16(default_inverse[j][i], &inverse_matrix[j][i]));
    366    }
    367  }
    368  for (int i = 0; i < 3; ++i) {
    369    JXL_QUIET_RETURN_IF_ERROR(visitor->F16(
    370        jxl::cms::kNegOpsinAbsorbanceBiasRGB[i], &opsin_biases[i]));
    371  }
    372  for (int i = 0; i < 4; ++i) {
    373    JXL_QUIET_RETURN_IF_ERROR(
    374        visitor->F16(kDefaultQuantBias[i], &quant_biases[i]));
    375  }
    376  return true;
    377 }
    378 
    379 ToneMapping::ToneMapping() { Bundle::Init(this); }
    380 Status ToneMapping::VisitFields(Visitor* JXL_RESTRICT visitor) {
    381  if (visitor->AllDefault(*this, &all_default)) {
    382    // Overwrite all serialized fields, but not any nonserialized_*.
    383    visitor->SetDefault(this);
    384    return true;
    385  }
    386 
    387  JXL_QUIET_RETURN_IF_ERROR(
    388      visitor->F16(kDefaultIntensityTarget, &intensity_target));
    389  if (intensity_target <= 0.f) {
    390    return JXL_FAILURE("invalid intensity target");
    391  }
    392 
    393  JXL_QUIET_RETURN_IF_ERROR(visitor->F16(0.0f, &min_nits));
    394  if (min_nits < 0.f || min_nits > intensity_target) {
    395    return JXL_FAILURE("invalid min %f vs max %f", min_nits, intensity_target);
    396  }
    397 
    398  JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &relative_to_max_display));
    399 
    400  JXL_QUIET_RETURN_IF_ERROR(visitor->F16(0.0f, &linear_below));
    401  if (linear_below < 0 || (relative_to_max_display && linear_below > 1.0f)) {
    402    return JXL_FAILURE("invalid linear_below %f (%s)", linear_below,
    403                       relative_to_max_display ? "relative" : "absolute");
    404  }
    405 
    406  return true;
    407 }
    408 
    409 Status ReadImageMetadata(BitReader* JXL_RESTRICT reader,
    410                         ImageMetadata* JXL_RESTRICT metadata) {
    411  return Bundle::Read(reader, metadata);
    412 }
    413 
    414 void ImageMetadata::SetAlphaBits(uint32_t bits, bool alpha_is_premultiplied) {
    415  std::vector<ExtraChannelInfo>& eciv = extra_channel_info;
    416  ExtraChannelInfo* alpha = Find(ExtraChannel::kAlpha);
    417  if (bits == 0) {
    418    if (alpha != nullptr) {
    419      // Remove the alpha channel from the extra channel info. It's
    420      // theoretically possible that there are multiple, remove all in that
    421      // case. This ensure a next HasAlpha() will return false.
    422      const auto is_alpha = [](const ExtraChannelInfo& eci) {
    423        return eci.type == ExtraChannel::kAlpha;
    424      };
    425      eciv.erase(std::remove_if(eciv.begin(), eciv.end(), is_alpha),
    426                 eciv.end());
    427    }
    428  } else {
    429    if (alpha == nullptr) {
    430      ExtraChannelInfo info;
    431      info.type = ExtraChannel::kAlpha;
    432      info.bit_depth.bits_per_sample = bits;
    433      info.dim_shift = 0;
    434      info.alpha_associated = alpha_is_premultiplied;
    435      // Prepend rather than append: in case there already are other extra
    436      // channels, prefer alpha channel to be listed first.
    437      eciv.insert(eciv.begin(), info);
    438    } else {
    439      // Ignores potential extra alpha channels, only sets to first one.
    440      alpha->bit_depth.bits_per_sample = bits;
    441      alpha->bit_depth.floating_point_sample = false;
    442      alpha->bit_depth.exponent_bits_per_sample = 0;
    443      alpha->alpha_associated = alpha_is_premultiplied;
    444    }
    445  }
    446  num_extra_channels = extra_channel_info.size();
    447  if (bits > 12) modular_16_bit_buffer_sufficient = false;
    448 }
    449 
    450 #if JXL_DEBUG_V_LEVEL >= 1
    451 std::string ImageMetadata::DebugString() const {
    452  std::ostringstream os;
    453  os << bit_depth.DebugString();
    454  if (modular_16_bit_buffer_sufficient) {
    455    os << " (modular 16)";
    456  }
    457  os << (xyb_encoded ? " xyb encoded" : " orig profile");
    458  os << " " << Description(color_encoding);
    459  if (num_extra_channels > 0) {
    460    os << " extra channels:";
    461    for (size_t i = 0; i < num_extra_channels; ++i) {
    462      os << " (" << extra_channel_info[i].DebugString() << ")";
    463      if (i + 1 < num_extra_channels) os << ",";
    464    }
    465  }
    466  if (have_preview) {
    467    os << " preview: " << preview_size.xsize() << "x" << preview_size.ysize();
    468  }
    469  if (orientation != 1) {
    470    os << " orientation: " << orientation;
    471  }
    472  return os.str();
    473 }
    474 
    475 std::string CodecMetadata::DebugString() const {
    476  std::ostringstream os;
    477  os << size.xsize() << "x" << size.ysize();
    478  os << " " << m.DebugString();
    479  return os.str();
    480 }
    481 #endif
    482 
    483 }  // namespace jxl