LibGfx: Add PGM image file type support

Author: https://github.com/asliturk
Commit: https://github.com/SerenityOS/serenity/commit/dc5b73c43a1
Pull-request: https://github.com/SerenityOS/serenity/pull/2633

Libraries/LibGfx/Bitmap.cpp

@@ -34,6 +34,7 @@
 #include <LibGfx/ICOLoader.h>
 #include <LibGfx/JPGLoader.h>
 #include <LibGfx/PBMLoader.h>
+#include <LibGfx/PGMLoader.h>
 #include <LibGfx/PNGLoader.h>
 #include <LibGfx/PPMLoader.h>
 #include <LibGfx/ShareableBitmap.h>

Libraries/LibGfx/Bitmap.h

@@ -35,6 +35,7 @@
 
 #define ENUMERATE_IMAGE_FORMATS           \
     __ENUMERATE_IMAGE_FORMAT(pbm, ".pbm") \
+    __ENUMERATE_IMAGE_FORMAT(pgm, ".pgm") \
     __ENUMERATE_IMAGE_FORMAT(png, ".png") \
     __ENUMERATE_IMAGE_FORMAT(ppm, ".ppm") \
     __ENUMERATE_IMAGE_FORMAT(gif, ".gif") \

Libraries/LibGfx/CMakeLists.txt

@@ -16,6 +16,7 @@ set(SOURCES
     Palette.cpp
     Path.cpp
     PBMLoader.cpp
+    PGMLoader.cpp
     PNGLoader.cpp
     PPMLoader.cpp
     Point.cpp

Libraries/LibGfx/ImageDecoder.cpp

@@ -30,6 +30,7 @@
 #include <LibGfx/ImageDecoder.h>
 #include <LibGfx/JPGLoader.h>
 #include <LibGfx/PBMLoader.h>
+#include <LibGfx/PGMLoader.h>
 #include <LibGfx/PNGLoader.h>
 #include <LibGfx/PPMLoader.h>
 
@@ -53,6 +54,10 @@ ImageDecoder::ImageDecoder(const u8* data, size_t size)
     if (m_plugin->sniff())
         return;
 
+    m_plugin = make<PGMImageDecoderPlugin>(data, size);
+    if (m_plugin->sniff())
+        return;
+
     m_plugin = make<PPMImageDecoderPlugin>(data, size);
     if (m_plugin->sniff())
         return;

Libraries/LibGfx/PGMLoader.cpp

@@ -0,0 +1,469 @@
+/*
+ * Copyright (c) 2020, Hüseyin ASLITÜRK <asliturk@hotmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "PGMLoader.h"
+#include <AK/LexicalPath.h>
+#include <AK/MappedFile.h>
+#include <AK/NetworkOrdered.h>
+#include <AK/StringBuilder.h>
+#include <string.h>
+
+namespace Gfx {
+
+struct PGMLoadingContext {
+    enum Type {
+        Unknown,
+        P2_ASCII,
+        P5_RAWBITS
+    };
+
+    enum State {
+        NotDecoded = 0,
+        Error,
+        MagicNumber,
+        Width,
+        Height,
+        Maxval,
+        Bitmap,
+        Decoded
+    };
+
+    Type type { Type::Unknown };
+    State state { State::NotDecoded };
+    const u8* data { nullptr };
+    size_t data_size { 0 };
+    u16 width { 0 };
+    u16 height { 0 };
+    u16 max_val { 0 };
+    RefPtr<Gfx::Bitmap> bitmap;
+};
+
+class Streamer {
+public:
+    Streamer(const u8* data, size_t size)
+        : m_data_ptr(data)
+        , m_size_remaining(size)
+    {
+    }
+
+    template<typename T>
+    bool read(T& value)
+    {
+        if (m_size_remaining < sizeof(T))
+            return false;
+        value = *((const NetworkOrdered<T>*)m_data_ptr);
+        m_data_ptr += sizeof(T);
+        m_size_remaining -= sizeof(T);
+        return true;
+    }
+
+    bool read_bytes(u8* buffer, size_t count)
+    {
+        if (m_size_remaining < count)
+            return false;
+        memcpy(buffer, m_data_ptr, count);
+        m_data_ptr += count;
+        m_size_remaining -= count;
+        return true;
+    }
+
+    bool at_end() const { return !m_size_remaining; }
+
+    void step_back()
+    {
+        m_data_ptr -= 1;
+        m_size_remaining += 1;
+    }
+
+private:
+    const u8* m_data_ptr { nullptr };
+    size_t m_size_remaining { 0 };
+};
+
+ALWAYS_INLINE static Color adjust_color(u16 max_val, Color& color)
+{
+    color.set_red((color.red() * 255) / max_val);
+    color.set_green((color.green() * 255) / max_val);
+    color.set_blue((color.blue() * 255) / max_val);
+
+    return color;
+}
+
+static bool read_number(Streamer& streamer, u16* value)
+{
+    u8 byte;
+    StringBuilder sb;
+
+    while (streamer.read(byte)) {
+        if (byte == ' ' || byte == '\t' || byte == '\n' || byte == '\r') {
+            streamer.step_back();
+            break;
+        }
+
+        sb.append(byte);
+    }
+
+    auto opt_value = sb.to_string().to_uint();
+    if (!opt_value.has_value()) {
+        return false;
+    }
+
+    *value = (u16)opt_value.value();
+    return true;
+}
+
+static bool read_comment(PGMLoadingContext& context, Streamer& streamer)
+{
+    (void)context;
+
+    bool exist = false;
+    u8 byte;
+
+    while (streamer.read(byte)) {
+        switch (byte) {
+        case '#': {
+            exist = true;
+            break;
+        }
+        case '\t':
+        case '\n': {
+            return exist;
+        }
+        default:
+            break;
+        }
+    }
+
+    return exist;
+}
+
+static bool read_magic_number(PGMLoadingContext& context, Streamer& streamer)
+{
+    if (context.state >= PGMLoadingContext::MagicNumber)
+        return true;
+
+    if (!context.data || context.data_size < 2) {
+        context.state = PGMLoadingContext::State::Error;
+        dbg() << "There is no enough data.";
+        return false;
+    }
+
+    u8 magic_number[2];
+    if (!streamer.read_bytes(magic_number, 2)) {
+        context.state = PGMLoadingContext::State::Error;
+        dbg() << "We can't read magic number.";
+        return false;
+    }
+
+    if (magic_number[0] == 'P' && magic_number[1] == '2') {
+        context.type = PGMLoadingContext::P2_ASCII;
+        context.state = PGMLoadingContext::MagicNumber;
+        return true;
+    }
+
+    if (magic_number[0] == 'P' && magic_number[1] == '5') {
+        context.type = PGMLoadingContext::P5_RAWBITS;
+        context.state = PGMLoadingContext::MagicNumber;
+        return true;
+    }
+
+    context.state = PGMLoadingContext::State::Error;
+    dbg() << "Magic number is not valid:" << (char)magic_number[0] << (char)magic_number[1];
+    return false;
+}
+
+static bool read_white_space(PGMLoadingContext& context, Streamer& streamer)
+{
+    bool exist = false;
+    u8 byte;
+
+    while (streamer.read(byte)) {
+        switch (byte) {
+        case ' ':
+        case '\t':
+        case '\n':
+        case '\r': {
+            exist = true;
+            break;
+        }
+        case '#': {
+            streamer.step_back();
+            read_comment(context, streamer);
+            break;
+        }
+        default: {
+            streamer.step_back();
+            return exist;
+        }
+        }
+    }
+
+    return exist;
+}
+
+static bool read_width(PGMLoadingContext& context, Streamer& streamer)
+{
+    bool result = read_number(streamer, &context.width);
+    if (!result || context.width == 0) {
+        return false;
+    }
+
+    context.state = PGMLoadingContext::Width;
+    return true;
+}
+
+static bool read_height(PGMLoadingContext& context, Streamer& streamer)
+{
+    bool result = read_number(streamer, &context.height);
+    if (!result || context.height == 0) {
+        return false;
+    }
+
+    context.state = PGMLoadingContext::Height;
+    return true;
+}
+
+static bool read_max_val(PGMLoadingContext& context, Streamer& streamer)
+{
+    bool result = read_number(streamer, &context.max_val);
+    if (!result || context.max_val == 0) {
+        return false;
+    }
+
+    if (context.max_val > 255) {
+        dbg() << "We can't pars 2 byte color.";
+        context.state = PGMLoadingContext::Error;
+        return false;
+    }
+
+    context.state = PGMLoadingContext::Maxval;
+    return true;
+}
+
+static bool read_image_data(PGMLoadingContext& context, Streamer& streamer)
+{
+    Vector<Gfx::Color> color_data;
+
+    if (context.type == PGMLoadingContext::P2_ASCII) {
+        u16 value;
+
+        while (true) {
+            if (!read_number(streamer, &value))
+                break;
+
+            if (!read_white_space(context, streamer))
+                break;
+
+            color_data.append({ (u8)value, (u8)value, (u8)value });
+        }
+    } else if (context.type == PGMLoadingContext::P5_RAWBITS) {
+        u8 pixel;
+        while (streamer.read(pixel)) {
+            color_data.append({ pixel, pixel, pixel });
+        }
+    }
+
+    context.bitmap = Bitmap::create_purgeable(BitmapFormat::RGB32, { context.width, context.height });
+
+    size_t index = 0;
+    for (int y = 0; y < context.height; ++y) {
+        for (int x = 0; x < context.width; ++x) {
+            Color color = color_data.at(index);
+            if (context.max_val < 255)
+                color = adjust_color(context.max_val, color);
+            context.bitmap->set_pixel(x, y, color);
+            index++;
+        }
+    }
+
+    context.state = PGMLoadingContext::State::Bitmap;
+    return true;
+}
+
+static bool decode_pgm(PGMLoadingContext& context)
+{
+    if (context.state >= PGMLoadingContext::State::Decoded)
+        return true;
+
+    Streamer streamer(context.data, context.data_size);
+
+    if (!read_magic_number(context, streamer))
+        return false;
+
+    if (!read_white_space(context, streamer))
+        return false;
+
+    if (!read_width(context, streamer))
+        return false;
+
+    if (!read_white_space(context, streamer))
+        return false;
+
+    if (!read_height(context, streamer))
+        return false;
+
+    if (!read_white_space(context, streamer))
+        return false;
+
+    if (!read_max_val(context, streamer))
+        return false;
+
+    if (!read_white_space(context, streamer))
+        return false;
+
+    if (!read_image_data(context, streamer))
+        return false;
+
+    context.state = PGMLoadingContext::State::Decoded;
+    return true;
+}
+
+static RefPtr<Gfx::Bitmap> load_pgm_impl(const u8* data, size_t data_size)
+{
+    PGMLoadingContext context;
+    context.data = data;
+    context.data_size = data_size;
+
+    if (!decode_pgm(context))
+        return nullptr;
+
+    return context.bitmap;
+}
+
+RefPtr<Gfx::Bitmap> load_pgm(const StringView& path)
+{
+    MappedFile mapped_file(path);
+    if (!mapped_file.is_valid()) {
+        return nullptr;
+    }
+
+    auto bitmap = load_pgm_impl((const u8*)mapped_file.data(), mapped_file.size());
+    if (bitmap)
+        bitmap->set_mmap_name(String::format("Gfx::Bitmap [%dx%d] - Decoded PGM: %s", bitmap->width(), bitmap->height(), LexicalPath::canonicalized_path(path).characters()));
+    return bitmap;
+}
+
+RefPtr<Gfx::Bitmap> load_pgm_from_memory(const u8* data, size_t length)
+{
+    auto bitmap = load_pgm_impl(data, length);
+    if (bitmap)
+        bitmap->set_mmap_name(String::format("Gfx::Bitmap [%dx%d] - Decoded PGM: <memory>", bitmap->width(), bitmap->height()));
+    return bitmap;
+}
+
+PGMImageDecoderPlugin::PGMImageDecoderPlugin(const u8* data, size_t size)
+{
+    m_context = make<PGMLoadingContext>();
+    m_context->data = data;
+    m_context->data_size = size;
+}
+
+PGMImageDecoderPlugin::~PGMImageDecoderPlugin()
+{
+}
+
+IntSize PGMImageDecoderPlugin::size()
+{
+    if (m_context->state == PGMLoadingContext::State::Error)
+        return {};
+
+    if (m_context->state < PGMLoadingContext::State::Decoded) {
+        bool success = decode_pgm(*m_context);
+        if (!success)
+            return {};
+    }
+
+    return { m_context->width, m_context->height };
+}
+
+RefPtr<Gfx::Bitmap> PGMImageDecoderPlugin::bitmap()
+{
+    if (m_context->state == PGMLoadingContext::State::Error)
+        return nullptr;
+
+    if (m_context->state < PGMLoadingContext::State::Decoded) {
+        bool success = decode_pgm(*m_context);
+        if (!success)
+            return nullptr;
+    }
+
+    ASSERT(m_context->bitmap);
+    return m_context->bitmap;
+}
+
+void PGMImageDecoderPlugin::set_volatile()
+{
+    if (m_context->bitmap)
+        m_context->bitmap->set_volatile();
+}
+
+bool PGMImageDecoderPlugin::set_nonvolatile()
+{
+    if (!m_context->bitmap)
+        return false;
+
+    return m_context->bitmap->set_nonvolatile();
+}
+
+bool PGMImageDecoderPlugin::sniff()
+{
+    if (m_context->data_size < 2)
+        return false;
+
+    if (m_context->data[0] == 'P' && m_context->data[1] == '2')
+        return true;
+
+    if (m_context->data[0] == 'P' && m_context->data[1] == '5')
+        return true;
+
+    return false;
+}
+
+bool PGMImageDecoderPlugin::is_animated()
+{
+    return false;
+}
+
+size_t PGMImageDecoderPlugin::loop_count()
+{
+    return 0;
+}
+
+size_t PGMImageDecoderPlugin::frame_count()
+{
+    return 1;
+}
+
+ImageFrameDescriptor PGMImageDecoderPlugin::frame(size_t i)
+{
+    if (i > 0) {
+        return { bitmap(), 0 };
+    }
+
+    return {};
+}
+
+}

Libraries/LibGfx/PGMLoader.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2020, Hüseyin ASLITÜRK <asliturk@hotmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <LibGfx/Bitmap.h>
+#include <LibGfx/ImageDecoder.h>
+
+namespace Gfx {
+
+RefPtr<Gfx::Bitmap> load_pgm(const StringView& path);
+RefPtr<Gfx::Bitmap> load_pgm_from_memory(const u8*, size_t);
+
+struct PGMLoadingContext;
+
+class PGMImageDecoderPlugin final : public ImageDecoderPlugin {
+public:
+    PGMImageDecoderPlugin(const u8*, size_t);
+    virtual ~PGMImageDecoderPlugin() override;
+
+    virtual IntSize size() override;
+    virtual RefPtr<Gfx::Bitmap> bitmap() override;
+
+    virtual void set_volatile() override;
+    [[nodiscard]] virtual bool set_nonvolatile() override;
+
+    virtual bool sniff() override;
+
+    virtual bool is_animated() override;
+    virtual size_t loop_count() override;
+    virtual size_t frame_count() override;
+    virtual ImageFrameDescriptor frame(size_t i) override;
+
+private:
+    OwnPtr<PGMLoadingContext> m_context;
+};
+
+}