avformat/image2: add Jpeg XL as image2 format

This commit adds support to libavformat for muxing
and demuxing Jpeg XL images as image2 streams.

1 files changed, 393 insertions, 0 deletions

diff --git a/libavformat/jpegxl_probe.c b/libavformat/jpegxl_probe.c
new file mode 100644
index 0000000000..924b529ad5
--- /dev/null
+++ b/libavformat/jpegxl_probe.c
@@ -0,0 +1,393 @@
+/*
+ * Jpeg XL header verification
+ * Copyright (c) 2022 Leo Izen <leo.izen@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "jpegxl_probe.h"
+
+#define BITSTREAM_READER_LE
+#include "libavcodec/get_bits.h"
+
+enum JpegXLExtraChannelType {
+    FF_JPEGXL_CT_ALPHA = 0,
+    FF_JPEGXL_CT_DEPTH,
+    FF_JPEGXL_CT_SPOT_COLOR,
+    FF_JPEGXL_CT_SELECTION_MASK,
+    FF_JPEGXL_CT_BLACK,
+    FF_JPEGXL_CT_CFA,
+    FF_JPEGXL_CT_THERMAL,
+    FF_JPEGXL_CT_NON_OPTIONAL = 15,
+    FF_JPEGXL_CT_OPTIONAL
+};
+
+enum JpegXLColorSpace {
+    FF_JPEGXL_CS_RGB = 0,
+    FF_JPEGXL_CS_GRAY,
+    FF_JPEGXL_CS_XYB,
+    FF_JPEGXL_CS_UNKNOWN
+};
+
+enum JpegXLWhitePoint {
+    FF_JPEGXL_WP_D65 = 1,
+    FF_JPEGXL_WP_CUSTOM,
+    FF_JPEGXL_WP_E = 10,
+    FF_JPEGXL_WP_DCI = 11
+};
+
+enum JpegXLPrimaries {
+    FF_JPEGXL_PR_SRGB = 1,
+    FF_JPEGXL_PR_CUSTOM,
+    FF_JPEGXL_PR_2100 = 9,
+    FF_JPEGXL_PR_P3 = 11,
+};
+
+#define jxl_bits(n) get_bits_long(gb, (n))
+#define jxl_bits_skip(n) skip_bits_long(gb, (n))
+#define jxl_u32(c0, c1, c2, c3, u0, u1, u2, u3) jpegxl_u32(gb, \
+    (const uint32_t[]){c0, c1, c2, c3}, (const uint32_t[]){u0, u1, u2, u3})
+#define jxl_u64() jpegxl_u64(gb)
+#define jxl_enum() jxl_u32(0, 1, 2, 18, 0, 0, 4, 6)
+
+/* read a U32(c_i + u(u_i)) */
+static uint32_t jpegxl_u32(GetBitContext *gb,
+                           const uint32_t constants[4], const uint32_t ubits[4])
+{
+    uint32_t ret, choice = jxl_bits(2);
+
+    ret = constants[choice];
+    if (ubits[choice])
+        ret += jxl_bits(ubits[choice]);
+
+    return ret;
+}
+
+/* read a U64() */
+static uint64_t jpegxl_u64(GetBitContext *gb)
+{
+    uint64_t shift = 12, ret;
+
+    switch (jxl_bits(2)) {
+    case 0:
+        ret = 0;
+        break;
+    case 1:
+        ret = 1 + jxl_bits(4);
+        break;
+    case 2:
+        ret = 17 + jxl_bits(8);
+        break;
+    case 3:
+        ret = jxl_bits(12);
+        while (jxl_bits(1)) {
+            if (shift < 60) {
+                ret |= jxl_bits(8) << shift;
+                shift += 8;
+            } else {
+                ret |= jxl_bits(4) << shift;
+                break;
+            }
+        }
+        break;
+    }
+
+    return ret;
+}
+
+static uint32_t jpegxl_width_from_ratio(uint32_t height, int ratio)
+{
+    uint64_t height64 = height; /* avoid integer overflow */
+    switch (ratio) {
+    case 1:
+        return height;
+    case 2:
+        return (uint32_t)((height64 * 12) / 10);
+    case 3:
+        return (uint32_t)((height64 * 4) / 3);
+    case 4:
+        return (uint32_t)((height64 * 3) / 2);
+    case 5:
+        return (uint32_t)((height64 * 16) / 9);
+    case 6:
+        return (uint32_t)((height64 * 5) / 4);
+    case 7:
+        return (uint32_t)(height64 * 2);
+    default:
+        break;
+    }
+
+    return 0; /* manual width */
+}
+
+/**
+ * validate a Jpeg XL Size Header
+ * @return >= 0 upon valid size, < 0 upon invalid size found
+ */
+static int jpegxl_read_size_header(GetBitContext *gb)
+{
+    uint32_t width, height;
+
+    if (jxl_bits(1)) {
+        /* small size header */
+        height = (jxl_bits(5) + 1) << 3;
+        width = jpegxl_width_from_ratio(height, jxl_bits(3));
+        if (!width)
+            width = (jxl_bits(5) + 1) << 3;
+    } else {
+        /* large size header */
+        height = 1 + jxl_u32(0, 0, 0, 0, 9, 13, 18, 30);
+        width = jpegxl_width_from_ratio(height, jxl_bits(3));
+        if (!width)
+            width = 1 + jxl_u32(0, 0, 0, 0, 9, 13, 18, 30);
+    }
+    if (width > (1 << 18) || height > (1 << 18)
+        || (width >> 4) * (height >> 4) > (1 << 20))
+        return -1;
+
+    return 0;
+}
+
+/**
+ * validate a Jpeg XL Preview Header
+ * @return >= 0 upon valid size, < 0 upon invalid size found
+ */
+static int jpegxl_read_preview_header(GetBitContext *gb)
+{
+    uint32_t width, height;
+
+    if (jxl_bits(1)) {
+        /* coded height and width divided by eight */
+        height = jxl_u32(16, 32, 1, 33, 0, 0, 5, 9) << 3;
+        width = jpegxl_width_from_ratio(height, jxl_bits(3));
+        if (!width)
+            width = jxl_u32(16, 32, 1, 33, 0, 0, 5, 9) << 3;
+    } else {
+        /* full height and width coded */
+        height = jxl_u32(1, 65, 321, 1345, 6, 8, 10, 12);
+        width = jpegxl_width_from_ratio(height, jxl_bits(3));
+        if (!width)
+            width = jxl_u32(1, 65, 321, 1345, 6, 8, 10, 12);
+    }
+    if (width > 4096 || height > 4096)
+        return -1;
+
+    return 0;
+}
+
+/**
+ * skip a Jpeg XL BitDepth Header. These cannot be invalid.
+ */
+static void jpegxl_skip_bit_depth(GetBitContext *gb)
+{
+    if (jxl_bits(1)) {
+        /* float samples */
+        jxl_u32(32, 16, 24, 1, 0, 0, 0, 6); /* mantissa */
+        jxl_bits_skip(4); /* exponent */
+    } else {
+        /* integer samples */
+        jxl_u32(8, 10, 12, 1, 0, 0, 0, 6);
+    }
+}
+
+/**
+ * validate a Jpeg XL Extra Channel Info bundle
+ * @return >= 0 upon valid, < 0 upon invalid
+ */
+static int jpegxl_read_extra_channel_info(GetBitContext *gb)
+{
+    int all_default = jxl_bits(1);
+    uint32_t type, name_len = 0;
+
+    if (!all_default) {
+        type = jxl_enum();
+        if (type > 63)
+            return -1; /* enum types cannot be 64+ */
+        if (type == FF_JPEGXL_CT_BLACK)
+            return -1;
+        jpegxl_skip_bit_depth(gb);
+        jxl_u32(0, 3, 4, 1, 0, 0, 0, 3); /* dim-shift */
+        /* max of name_len is 1071 = 48 + 2^10 - 1 */
+        name_len = jxl_u32(0, 0, 16, 48, 0, 4, 5, 10);
+    } else {
+        type = FF_JPEGXL_CT_ALPHA;
+    }
+
+    /* skip over the name */
+    jxl_bits_skip(8 * name_len);
+
+    if (!all_default && type == FF_JPEGXL_CT_ALPHA)
+        jxl_bits_skip(1);
+
+    if (type == FF_JPEGXL_CT_SPOT_COLOR)
+        jxl_bits_skip(16 * 4);
+
+    if (type == FF_JPEGXL_CT_CFA)
+        jxl_u32(1, 0, 3, 19, 0, 2, 4, 8);
+
+    return 0;
+}
+
+/* verify that a codestream header is valid */
+int ff_jpegxl_verify_codestream_header(const uint8_t *buf, int buflen)
+{
+    GetBitContext gbi, *gb = &gbi;
+    int all_default, extra_fields = 0;
+    int xyb_encoded = 1, have_icc_profile = 0;
+    uint32_t num_extra_channels;
+    uint64_t extensions;
+
+    init_get_bits8(gb, buf, buflen);
+
+    if (jxl_bits(16) != FF_JPEGXL_CODESTREAM_SIGNATURE_LE)
+        return -1;
+
+    if (jpegxl_read_size_header(gb) < 0)
+        return -1;
+
+    all_default = jxl_bits(1);
+    if (!all_default)
+        extra_fields = jxl_bits(1);
+
+    if (extra_fields) {
+        jxl_bits_skip(3); /* orientation */
+
+        /*
+         * intrinstic size
+         * any size header here is valid, but as it
+         * is variable length we have to read it
+         */
+        if (jxl_bits(1))
+            jpegxl_read_size_header(gb);
+
+        /* preview header */
+        if (jxl_bits(1)) {
+            if (jpegxl_read_preview_header(gb) < 0)
+                return -1;
+        }
+
+        /* animation header */
+        if (jxl_bits(1)) {
+            jxl_u32(100, 1000, 1, 1, 0, 0, 10, 30);
+            jxl_u32(1, 1001, 1, 1, 0, 0, 8, 10);
+            jxl_u32(0, 0, 0, 0, 0, 3, 16, 32);
+            jxl_bits_skip(1);
+        }
+    }
+
+    if (!all_default) {
+        jpegxl_skip_bit_depth(gb);
+
+        /* modular_16bit_buffers must equal 1 */
+        if (!jxl_bits(1))
+            return -1;
+
+        num_extra_channels = jxl_u32(0, 1, 2, 1, 0, 0, 4, 12);
+        if (num_extra_channels > 4)
+            return -1;
+        for (uint32_t i = 0; i < num_extra_channels; i++) {
+            if (jpegxl_read_extra_channel_info(gb) < 0)
+                return -1;
+        }
+
+        xyb_encoded = jxl_bits(1);
+
+        /* color encoding bundle */
+        if (!jxl_bits(1)) {
+            uint32_t color_space;
+            have_icc_profile = jxl_bits(1);
+            color_space = jxl_enum();
+            if (color_space > 63)
+                return -1;
+
+            if (!have_icc_profile) {
+                if (color_space != FF_JPEGXL_CS_XYB) {
+                    uint32_t white_point = jxl_enum();
+                    if (white_point > 63)
+                        return -1;
+                    if (white_point == FF_JPEGXL_WP_CUSTOM) {
+                        /* ux and uy values */
+                        jxl_u32(0, 524288, 1048576, 2097152, 19, 19, 20, 21);
+                        jxl_u32(0, 524288, 1048576, 2097152, 19, 19, 20, 21);
+                    }
+                    if (color_space != FF_JPEGXL_CS_GRAY) {
+                        /* primaries */
+                        uint32_t primaries = jxl_enum();
+                        if (primaries > 63)
+                            return -1;
+                        if (primaries == FF_JPEGXL_PR_CUSTOM) {
+                            /* ux/uy values for r,g,b */
+                            for (int i = 0; i < 6; i++)
+                                jxl_u32(0, 524288, 1048576, 2097152, 19, 19, 20, 21);
+                        }
+                    }
+                }
+
+                /* transfer characteristics */
+                if (jxl_bits(1)) {
+                    /* gamma */
+                    jxl_bits_skip(24);
+                } else {
+                    /* transfer function */
+                    if (jxl_enum() > 63)
+                        return -1;
+                }
+
+                /* rendering intent */
+                if (jxl_enum() > 63)
+                    return -1;
+            }
+        }
+
+        /* tone mapping bundle */
+        if (extra_fields && !jxl_bits(1))
+            jxl_bits_skip(16 + 16 + 1 + 16);
+
+        extensions = jxl_u64();
+        if (extensions) {
+            for (int i = 0; i < 64; i++) {
+                if (extensions & (UINT64_C(1) << i))
+                    jxl_u64();
+            }
+        }
+    }
+
+    /* default transform */
+    if (!jxl_bits(1)) {
+        /* opsin inverse matrix */
+        if (xyb_encoded && !jxl_bits(1))
+            jxl_bits_skip(16 * 16);
+        /* cw_mask and default weights */
+        if (jxl_bits(1))
+            jxl_bits_skip(16 * 15);
+        if (jxl_bits(1))
+            jxl_bits_skip(16 * 55);
+        if (jxl_bits(1))
+            jxl_bits_skip(16 * 210);
+    }
+
+    if (!have_icc_profile) {
+        int bits_remaining = 7 - (get_bits_count(gb) - 1) % 8;
+        if (bits_remaining && jxl_bits(bits_remaining))
+            return -1;
+    }
+
+    if (get_bits_left(gb) < 0)
+        return -1;
+
+    return 0;
+}