/* Copyright 2010 Larry Gritz and the other authors and contributors. All Rights Reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * 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. * Neither the name of the software's owners nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. 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 OWNER 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. (This is the Modified BSD License) */ #include "sgi_pvt.h" #include OIIO_PLUGIN_NAMESPACE_BEGIN // Obligatory material to make this a recognizeable imageio plugin: OIIO_PLUGIN_EXPORTS_BEGIN OIIO_EXPORT int sgi_imageio_version = OIIO_PLUGIN_VERSION; OIIO_EXPORT const char* sgi_imageio_library_version() { return nullptr; } OIIO_EXPORT ImageInput* sgi_input_imageio_create() { return new SgiInput; } OIIO_EXPORT const char* sgi_input_extensions[] = { "sgi", "rgb", "rgba", "bw", "int", "inta", nullptr }; OIIO_PLUGIN_EXPORTS_END bool SgiInput::valid_file(const std::string& filename) const { FILE* fd = Filesystem::fopen(filename, "rb"); if (!fd) return false; int16_t magic; bool ok = (::fread(&magic, sizeof(magic), 1, fd) == 1) && (magic == sgi_pvt::SGI_MAGIC); fclose(fd); return ok; } bool SgiInput::open(const std::string& name, ImageSpec& spec) { // saving name for later use m_filename = name; m_fd = Filesystem::fopen(m_filename, "rb"); if (!m_fd) { error("Could not open file \"%s\"", name.c_str()); return false; } if (!read_header()) return false; if (m_sgi_header.magic != sgi_pvt::SGI_MAGIC) { error("\"%s\" is not a SGI file, magic number doesn't match", m_filename.c_str()); close(); return false; } int height = 0; int nchannels = 0; switch (m_sgi_header.dimension) { case sgi_pvt::ONE_SCANLINE_ONE_CHANNEL: height = 1; nchannels = 1; break; case sgi_pvt::MULTI_SCANLINE_ONE_CHANNEL: height = m_sgi_header.ysize; nchannels = 1; break; case sgi_pvt::MULTI_SCANLINE_MULTI_CHANNEL: height = m_sgi_header.ysize; nchannels = m_sgi_header.zsize; break; default: error("Bad dimension: %d", m_sgi_header.dimension); close(); return false; } if (m_sgi_header.colormap == sgi_pvt::COLORMAP || m_sgi_header.colormap == sgi_pvt::SCREEN) { error("COLORMAP and SCREEN color map types aren't supported"); close(); return false; } m_spec = ImageSpec(m_sgi_header.xsize, height, nchannels, m_sgi_header.bpc == 1 ? TypeDesc::UINT8 : TypeDesc::UINT16); if (strlen(m_sgi_header.imagename)) m_spec.attribute("ImageDescription", m_sgi_header.imagename); if (m_sgi_header.storage == sgi_pvt::RLE) { m_spec.attribute("compression", "rle"); if (!read_offset_tables()) return false; } spec = m_spec; return true; } bool SgiInput::read_native_scanline(int subimage, int miplevel, int y, int z, void* data) { lock_guard lock(m_mutex); if (!seek_subimage(subimage, miplevel)) return false; if (y < 0 || y > m_spec.height) return false; y = m_spec.height - y - 1; int bpc = m_sgi_header.bpc; std::vector> channeldata(m_spec.nchannels); if (m_sgi_header.storage == sgi_pvt::RLE) { // reading and uncompressing first channel (red in RGBA images) for (int c = 0; c < m_spec.nchannels; ++c) { int off = y + c * m_spec.height; // offset for this scanline/channel int scanline_offset = start_tab[off]; int scanline_length = length_tab[off]; channeldata[c].resize(m_spec.width * bpc); uncompress_rle_channel(scanline_offset, scanline_length, &(channeldata[c][0])); } } else { // non-RLE case -- just read directly into our channel data for (int c = 0; c < m_spec.nchannels; ++c) { int off = y + c * m_spec.height; // offset for this scanline/channel int scanline_offset = sgi_pvt::SGI_HEADER_LEN + off * m_spec.width * bpc; fseek(m_fd, scanline_offset, SEEK_SET); channeldata[c].resize(m_spec.width * bpc); if (!fread(&(channeldata[c][0]), 1, m_spec.width * bpc)) return false; } } if (m_spec.nchannels == 1) { // If just one channel, no interleaving is necessary, just memcpy memcpy(data, &(channeldata[0][0]), channeldata[0].size()); } else { unsigned char* cdata = (unsigned char*)data; for (int x = 0; x < m_spec.width; ++x) { for (int c = 0; c < m_spec.nchannels; ++c) { *cdata++ = channeldata[c][x * bpc]; if (bpc == 2) *cdata++ = channeldata[c][x * bpc + 1]; } } } // Swap endianness if needed if (bpc == 2 && littleendian()) swap_endian((unsigned short*)data, m_spec.width * m_spec.nchannels); return true; } bool SgiInput::uncompress_rle_channel(int scanline_off, int scanline_len, unsigned char* out) { int bpc = m_sgi_header.bpc; std::vector rle_scanline(scanline_len); fseek(m_fd, scanline_off, SEEK_SET); if (!fread(&rle_scanline[0], 1, scanline_len)) return false; int limit = m_spec.width; int i = 0; if (bpc == 1) { // 1 bit per channel while (i < scanline_len) { // Read a byte, it is the count. unsigned char value = rle_scanline[i++]; int count = value & 0x7F; // If the count is zero, we're done if (!count) break; // If the high bit is set, we just copy the next 'count' values if (value & 0x80) { while (count--) { DASSERT(i < scanline_len && limit > 0); *(out++) = rle_scanline[i++]; --limit; } } // If the high bit is zero, we copy the NEXT value, count times else { value = rle_scanline[i++]; while (count--) { DASSERT(limit > 0); *(out++) = value; --limit; } } } } else { // 2 bits per channel ASSERT(bpc == 2); while (i < scanline_len) { // Read a byte, it is the count. unsigned short value = (rle_scanline[i] << 8) | rle_scanline[i + 1]; i += 2; int count = value & 0x7F; // If the count is zero, we're done if (!count) break; // If the high bit is set, we just copy the next 'count' values if (value & 0x80) { while (count--) { DASSERT(i + 1 < scanline_len && limit > 0); *(out++) = rle_scanline[i++]; *(out++) = rle_scanline[i++]; --limit; } } // If the high bit is zero, we copy the NEXT value, count times else { while (count--) { DASSERT(limit > 0); *(out++) = rle_scanline[i]; *(out++) = rle_scanline[i + 1]; --limit; } i += 2; } } } if (i != scanline_len || limit != 0) { error("Corrupt RLE data"); return false; } return true; } bool SgiInput::close() { if (m_fd) fclose(m_fd); init(); return true; } bool SgiInput::read_header() { if (!fread(&m_sgi_header.magic, sizeof(m_sgi_header.magic), 1) || !fread(&m_sgi_header.storage, sizeof(m_sgi_header.storage), 1) || !fread(&m_sgi_header.bpc, sizeof(m_sgi_header.bpc), 1) || !fread(&m_sgi_header.dimension, sizeof(m_sgi_header.dimension), 1) || !fread(&m_sgi_header.xsize, sizeof(m_sgi_header.xsize), 1) || !fread(&m_sgi_header.ysize, sizeof(m_sgi_header.ysize), 1) || !fread(&m_sgi_header.zsize, sizeof(m_sgi_header.zsize), 1) || !fread(&m_sgi_header.pixmin, sizeof(m_sgi_header.pixmin), 1) || !fread(&m_sgi_header.pixmax, sizeof(m_sgi_header.pixmax), 1) || !fread(&m_sgi_header.dummy, sizeof(m_sgi_header.dummy), 1) || !fread(&m_sgi_header.imagename, sizeof(m_sgi_header.imagename), 1)) return false; m_sgi_header.imagename[79] = '\0'; if (!fread(&m_sgi_header.colormap, sizeof(m_sgi_header.colormap), 1)) return false; //don't read dummy bytes fseek(m_fd, 404, SEEK_CUR); if (littleendian()) { swap_endian(&m_sgi_header.magic); swap_endian(&m_sgi_header.dimension); swap_endian(&m_sgi_header.xsize); swap_endian(&m_sgi_header.ysize); swap_endian(&m_sgi_header.zsize); swap_endian(&m_sgi_header.pixmin); swap_endian(&m_sgi_header.pixmax); swap_endian(&m_sgi_header.colormap); } return true; } bool SgiInput::read_offset_tables() { int tables_size = m_sgi_header.ysize * m_sgi_header.zsize; start_tab.resize(tables_size); length_tab.resize(tables_size); if (!fread(&start_tab[0], sizeof(uint32_t), tables_size) || !fread(&length_tab[0], sizeof(uint32_t), tables_size)) return false; if (littleendian()) { swap_endian(&length_tab[0], length_tab.size()); swap_endian(&start_tab[0], start_tab.size()); } return true; } OIIO_PLUGIN_NAMESPACE_END