Exemplo n.º 1
0
/**
   Write a chunk in a PNG stream from the current position.
   @param chunk_name Name of the chunk
   @param chunk_data Chunk array
   @param length Chunk length
   @param hPngMemory PNG stream handle
*/
static void
mng_WriteChunk(BYTE *chunk_name, BYTE *chunk_data, DWORD length, FIMEMORY *hPngMemory) {
    DWORD crc_file = 0;
    // write a PNG chunk ...
    // - length
    mng_SwapLong(&length);
    FreeImage_WriteMemory(&length, 1, 4, hPngMemory);
    mng_SwapLong(&length);
    // - chunk name
    FreeImage_WriteMemory(chunk_name, 1, 4, hPngMemory);
    if(chunk_data && length) {
        // - chunk data
        FreeImage_WriteMemory(chunk_data, 1, length, hPngMemory);
        // - crc
        crc_file = FreeImage_ZLibCRC32(0, chunk_name, 4);
        crc_file = FreeImage_ZLibCRC32(crc_file, chunk_data, length);
        mng_SwapLong(&crc_file);
        FreeImage_WriteMemory(&crc_file, 1, 4, hPngMemory);
    } else {
        // - crc
        crc_file = FreeImage_ZLibCRC32(0, chunk_name, 4);
        mng_SwapLong(&crc_file);
        FreeImage_WriteMemory(&crc_file, 1, 4, hPngMemory);
    }

}
Exemplo n.º 2
0
/**
   Wrap a IDAT chunk as a PNG stream.
   The stream has the structure { g_png_signature, IHDR, IDAT, IEND }
   The image is assumed to be a greyscale image.

   @param jng_width Image width
   @param jng_height Image height
   @param jng_alpha_sample_depth Bits per pixel
   @param mChunk PNG grayscale IDAT format
   @param mLength IDAT chunk length
   @param hPngMemory Output memory stream
*/
static void
mng_WritePNGStream(DWORD jng_width, DWORD jng_height, BYTE jng_alpha_sample_depth, BYTE *mChunk, DWORD mLength, FIMEMORY *hPngMemory) {
    // PNG grayscale IDAT format

    BYTE data[14];

    // wrap the IDAT chunk as a PNG stream

    // write PNG file signature
    FreeImage_WriteMemory(g_png_signature, 1, 8, hPngMemory);

    // write a IHDR chunk ...
    /*
      The IHDR chunk must appear FIRST. It contains:
      Width:              4 bytes
      Height:             4 bytes
      Bit depth:          1 byte
      Color type:         1 byte
      Compression method: 1 byte
      Filter method:      1 byte
      Interlace method:   1 byte
    */
    // - chunk data
    mng_SwapLong(&jng_width);
    mng_SwapLong(&jng_height);
    memcpy(&data[0], &jng_width, 4);
    memcpy(&data[4], &jng_height, 4);
    mng_SwapLong(&jng_width);
    mng_SwapLong(&jng_height);
    data[8] = jng_alpha_sample_depth;
    data[9] = 0;    // color_type gray (jng_color_type)
    data[10] = 0;   // compression method 0 (jng_alpha_compression_method)
    data[11] = 0;   // filter_method 0 (jng_alpha_filter_method)
    data[12] = 0;   // interlace_method 0 (jng_alpha_interlace_method)

    mng_WriteChunk(mng_IHDR, &data[0], 13, hPngMemory);

    // write a IDAT chunk ...
    mng_WriteChunk(mng_IDAT, mChunk, mLength, hPngMemory);

    // write a IEND chunk ...
    mng_WriteChunk(mng_IEND, NULL, 0, hPngMemory);

}
Exemplo n.º 3
0
/**
Retrieve the position of a chunk in a PNG stream
@param hPngMemory PNG stream handle
@param chunk_name Name of the chunk to be found
@param offset Start of the search in the stream
@param start_pos [returned value] Start position of the chunk
@param next_pos [returned value] Start position of the next chunk
@return Returns TRUE if successful, returns FALSE otherwise
*/
static BOOL 
mng_FindChunk(FIMEMORY *hPngMemory, BYTE *chunk_name, long offset, DWORD *start_pos, DWORD *next_pos) {
	BOOL mEnd = FALSE;
	DWORD mLength = 0;

	BYTE *data = NULL;
	DWORD size_in_bytes = 0;

	*start_pos = 0;
	*next_pos = 0;

	// get a pointer to the stream buffer
	FreeImage_AcquireMemory(hPngMemory, &data, &size_in_bytes);
	if(!(data && size_in_bytes) || (size_in_bytes < 20) || (size_in_bytes - offset < 20)) {
		// not enough space to read a signature(8 bytes) + a chunk(at least 12 bytes)
		return FALSE;
	}

	try {
	
		// skip the signature and/or any following chunk(s)
		DWORD chunk_pos = offset;

		while(1) {
			// get chunk length
			if(chunk_pos + 4 > size_in_bytes) {
				break;
			}

			memcpy(&mLength, &data[chunk_pos], 4);
			mng_SwapLong(&mLength);
			chunk_pos += 4;

			const DWORD next_chunk_pos = chunk_pos + 4 + mLength + 4;
			if(next_chunk_pos > size_in_bytes) {
				break;
			}

			// get chunk name
			if(memcmp(&data[chunk_pos], chunk_name, 4) == 0) {
				chunk_pos -= 4;	// found chunk
				*start_pos = chunk_pos;
				*next_pos = next_chunk_pos;
				return TRUE;
			}
			
			chunk_pos = next_chunk_pos;
		}

		return FALSE;

	} catch(int) {
		return FALSE;
	}
}
Exemplo n.º 4
0
/**
   Load a FIBITMAP from a MNG or a JNG stream
   @param format_id ID of the caller
   @param io Stream i/o functions
   @param handle Stream handle
   @param Offset Start of the first chunk
   @param flags Loading flags
   @return Returns a dib if successful, returns NULL otherwise
*/
FIBITMAP*
mng_ReadChunks(int format_id, FreeImageIO *io, fi_handle handle, long Offset, int flags = 0) {
    DWORD mLength = 0;
    BYTE mChunkName[5];
    BYTE *mChunk = NULL;
    DWORD crc_file;
    long LastOffset;
    long mOrigPos;
    BYTE *PLTE_file_chunk = NULL;   // whole PLTE chunk (lentgh, name, array, crc)
    DWORD PLTE_file_size = 0;       // size of PLTE chunk

    BOOL m_HasGlobalPalette = FALSE; // may turn to TRUE in PLTE chunk
    unsigned m_TotalBytesOfChunks = 0;
    FIBITMAP *dib = NULL;
    FIBITMAP *dib_alpha = NULL;

    FIMEMORY *hJpegMemory = NULL;
    FIMEMORY *hPngMemory = NULL;
    FIMEMORY *hIDATMemory = NULL;

    // ---
    DWORD jng_width = 0;
    DWORD jng_height = 0;
    BYTE jng_color_type = 0;
    BYTE jng_image_sample_depth = 0;
    BYTE jng_image_compression_method = 0;

    BYTE jng_alpha_sample_depth = 0;
    BYTE jng_alpha_compression_method = 0;
    BYTE jng_alpha_filter_method = 0;
    BYTE jng_alpha_interlace_method = 0;

    DWORD mng_frame_width = 0;
    DWORD mng_frame_height = 0;
    DWORD mng_ticks_per_second = 0;
    DWORD mng_nominal_layer_count = 0;
    DWORD mng_nominal_frame_count = 0;
    DWORD mng_nominal_play_time = 0;
    DWORD mng_simplicity_profile = 0;


    DWORD res_x = 2835; // 72 dpi
    DWORD res_y = 2835; // 72 dpi
    RGBQUAD rgbBkColor = {0, 0, 0, 0};
    WORD bk_red, bk_green, bk_blue;
    BOOL hasBkColor = FALSE;
    BOOL mHasIDAT = FALSE;

    tEXtMAP key_value_pair;

    // ---

    BOOL header_only = (flags & FIF_LOAD_NOPIXELS) == FIF_LOAD_NOPIXELS;

    // get the file size
    const long mLOF = mng_LOF(io, handle);
    // go to the first chunk
    io->seek_proc(handle, Offset, SEEK_SET);

    try {
        BOOL mEnd = FALSE;

        while(mEnd == FALSE) {
            // start of the chunk
            LastOffset = io->tell_proc(handle);
            // read length
            mLength = 0;
            io->read_proc(&mLength, 1, sizeof(mLength), handle);
            mng_SwapLong(&mLength);
            // read name
            io->read_proc(&mChunkName[0], 1, 4, handle);
            mChunkName[4] = '\0';

            if(mLength > 0) {
                mChunk = (BYTE*)realloc(mChunk, mLength);
                if(!mChunk) {
                    FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: out of memory", mChunkName);
                    throw (const char*)NULL;
                }
                Offset = io->tell_proc(handle);
                if(Offset + (long)mLength > mLOF) {
                    FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: unexpected end of file", mChunkName);
                    throw (const char*)NULL;
                }
                // read chunk
                io->read_proc(mChunk, 1, mLength, handle);
            }
            // read crc
            io->read_proc(&crc_file, 1, sizeof(crc_file), handle);
            mng_SwapLong(&crc_file);
            // check crc
            DWORD crc_check = FreeImage_ZLibCRC32(0, &mChunkName[0], 4);
            crc_check = FreeImage_ZLibCRC32(crc_check, mChunk, mLength);
            if(crc_check != crc_file) {
                FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: bad CRC", mChunkName);
                throw (const char*)NULL;
            }

            switch( mng_GetChunckType(mChunkName) ) {
                case MHDR:
                    // The MHDR chunk is always first in all MNG datastreams except for those
                    // that consist of a single PNG or JNG datastream with a PNG or JNG signature.
                    if(mLength == 28) {
                        memcpy(&mng_frame_width, &mChunk[0], 4);
                        memcpy(&mng_frame_height, &mChunk[4], 4);
                        memcpy(&mng_ticks_per_second, &mChunk[8], 4);
                        memcpy(&mng_nominal_layer_count, &mChunk[12], 4);
                        memcpy(&mng_nominal_frame_count, &mChunk[16], 4);
                        memcpy(&mng_nominal_play_time, &mChunk[20], 4);
                        memcpy(&mng_simplicity_profile, &mChunk[24], 4);

                        mng_SwapLong(&mng_frame_width);
                        mng_SwapLong(&mng_frame_height);
                        mng_SwapLong(&mng_ticks_per_second);
                        mng_SwapLong(&mng_nominal_layer_count);
                        mng_SwapLong(&mng_nominal_frame_count);
                        mng_SwapLong(&mng_nominal_play_time);
                        mng_SwapLong(&mng_simplicity_profile);

                    } else {
                        FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: size is %d instead of 28", mChunkName, mLength);
                    }
                    break;

                case MEND:
                    mEnd = TRUE;
                    break;

                case LOOP:
                case ENDL:
                    break;
                case DEFI:
                    break;
                case SAVE:
                case SEEK:
                case TERM:
                    break;
                case BACK:
                    break;

                    // Global "PLTE" and "tRNS" (if any).  PNG "PLTE" will be of 0 byte, as it uses global data.
                case PLTE:  // Global
                    m_HasGlobalPalette = TRUE;
                    PLTE_file_size = mLength + 12; // (lentgh, name, array, crc) = (4, 4, mLength, 4)
                    PLTE_file_chunk = (BYTE*)realloc(PLTE_file_chunk, PLTE_file_size);
                    if(!PLTE_file_chunk) {
                        FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: out of memory", mChunkName);
                        throw (const char*)NULL;
                    } else {
                        mOrigPos = io->tell_proc(handle);
                        // seek to the start of the chunk
                        io->seek_proc(handle, LastOffset, SEEK_SET);
                        // load the whole chunk
                        io->read_proc(PLTE_file_chunk, 1, PLTE_file_size, handle);
                        // go to the start of the next chunk
                        io->seek_proc(handle, mOrigPos, SEEK_SET);
                    }
                    break;

                case tRNS:  // Global
                    break;

                case IHDR:
                    Offset = LastOffset;
                    // parse the PNG file and get its file size
                    if(mng_CountPNGChunks(io, handle, Offset, &m_TotalBytesOfChunks) == FALSE) {
                        // reach an unexpected end of file
                        mEnd = TRUE;
                        FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: unexpected end of PNG file", mChunkName);
                        break;
                    }

                    // wrap the { IHDR, ..., IEND } chunks as a PNG stream
                    if(hPngMemory == NULL) {
                        hPngMemory = FreeImage_OpenMemory();
                    }

                    mOrigPos = io->tell_proc(handle);

                    // write PNG file signature
                    FreeImage_SeekMemory(hPngMemory, 0, SEEK_SET);
                    FreeImage_WriteMemory(g_png_signature, 1, 8, hPngMemory);

                    mChunk = (BYTE*)realloc(mChunk, m_TotalBytesOfChunks);
                    if(!mChunk) {
                        FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: out of memory", mChunkName);
                        throw (const char*)NULL;
                    }

                    // on calling CountPNGChunks earlier, we were in Offset pos,
                    // go back there
                    io->seek_proc(handle, Offset, SEEK_SET);
                    io->read_proc(mChunk, 1, m_TotalBytesOfChunks, handle);
                    // Put back to original pos
                    io->seek_proc(handle, mOrigPos, SEEK_SET);
                    // write the PNG chunks
                    FreeImage_WriteMemory(mChunk, 1, m_TotalBytesOfChunks, hPngMemory);

                    // plug in global PLTE if local PLTE exists
                    if(m_HasGlobalPalette) {
                        // ensure we remove some local chunks, so that global
                        // "PLTE" can be inserted right before "IDAT".
                        mng_RemoveChunk(hPngMemory, mng_PLTE);
                        mng_RemoveChunk(hPngMemory, mng_tRNS);
                        mng_RemoveChunk(hPngMemory, mng_bKGD);
                        // insert global "PLTE" chunk in its entirety before "IDAT"
                        mng_InsertChunk(hPngMemory, mng_IDAT, PLTE_file_chunk, PLTE_file_size);
                    }

                    if(dib) FreeImage_Unload(dib);
                    dib = mng_LoadFromMemoryHandle(hPngMemory, flags);

                    // stop after the first image
                    mEnd = TRUE;
                    break;

                case JHDR:
                    if(mLength == 16) {
                        memcpy(&jng_width, &mChunk[0], 4);
                        memcpy(&jng_height, &mChunk[4], 4);
                        mng_SwapLong(&jng_width);
                        mng_SwapLong(&jng_height);

                        jng_color_type = mChunk[8];
                        jng_image_sample_depth = mChunk[9];
                        jng_image_compression_method = mChunk[10];
                        //BYTE jng_image_interlace_method = mChunk[11]; // for debug only

                        jng_alpha_sample_depth = mChunk[12];
                        jng_alpha_compression_method = mChunk[13];
                        jng_alpha_filter_method = mChunk[14];
                        jng_alpha_interlace_method = mChunk[15];
                    } else {
                        FreeImage_OutputMessageProc(format_id, "Error while parsing %s chunk: invalid chunk length", mChunkName);
                        throw (const char*)NULL;
                    }
                    break;

                case JDAT:
                    if(hJpegMemory == NULL) {
                        hJpegMemory = FreeImage_OpenMemory();
                    }
                    // as there may be several JDAT chunks, concatenate them
                    FreeImage_WriteMemory(mChunk, 1, mLength, hJpegMemory);
                    break;

                case IDAT:
                    if(!header_only && (jng_alpha_compression_method == 0)) {
                        // PNG grayscale IDAT format
                        if(hIDATMemory == NULL) {
                            hIDATMemory = FreeImage_OpenMemory();
                            mHasIDAT = TRUE;
                        }
                        // as there may be several IDAT chunks, concatenate them
                        FreeImage_WriteMemory(mChunk, 1, mLength, hIDATMemory);
                    }
                    break;

                case IEND:
                    if(!hJpegMemory) {
                        mEnd = TRUE;
                        break;
                    }
                    // load the JPEG
                    if(dib) {
                        FreeImage_Unload(dib);
                    }
                    dib = mng_LoadFromMemoryHandle(hJpegMemory, flags);

                    // load the PNG alpha layer
                    if(mHasIDAT) {
                        BYTE *data = NULL;
                        DWORD size_in_bytes = 0;

                        // get a pointer to the IDAT buffer
                        FreeImage_AcquireMemory(hIDATMemory, &data, &size_in_bytes);
                        if(data && size_in_bytes) {
                            // wrap the IDAT chunk as a PNG stream
                            if(hPngMemory == NULL) {
                                hPngMemory = FreeImage_OpenMemory();
                            }
                            mng_WritePNGStream(jng_width, jng_height, jng_alpha_sample_depth, data, size_in_bytes, hPngMemory);
                            // load the PNG
                            if(dib_alpha) {
                                FreeImage_Unload(dib_alpha);
                            }
                            dib_alpha = mng_LoadFromMemoryHandle(hPngMemory, flags);
                        }
                    }
                    // stop the parsing
                    mEnd = TRUE;
                    break;

                case JDAA:
                    break;

                case gAMA:
                    break;

                case pHYs:
                    // unit is pixels per meter
                    memcpy(&res_x, &mChunk[0], 4);
                    mng_SwapLong(&res_x);
                    memcpy(&res_y, &mChunk[4], 4);
                    mng_SwapLong(&res_y);
                    break;

                case bKGD:
                    memcpy(&bk_red, &mChunk[0], 2);
                    mng_SwapShort(&bk_red);
                    rgbBkColor.rgbRed = (BYTE)bk_red;
                    memcpy(&bk_green, &mChunk[2], 2);
                    mng_SwapShort(&bk_green);
                    rgbBkColor.rgbGreen = (BYTE)bk_green;
                    memcpy(&bk_blue, &mChunk[4], 2);
                    mng_SwapShort(&bk_blue);
                    rgbBkColor.rgbBlue = (BYTE)bk_blue;
                    hasBkColor = TRUE;
                    break;

                case tEXt:
                    mng_SetMetadata_tEXt(key_value_pair, mChunk, mLength);
                    break;

                case UNKNOWN_CHUNCK:
                default:
                    break;


            } // switch( GetChunckType )
        } // while(!mEnd)

        FreeImage_CloseMemory(hJpegMemory);
        FreeImage_CloseMemory(hPngMemory);
        FreeImage_CloseMemory(hIDATMemory);
        free(mChunk);
        free(PLTE_file_chunk);

        // convert to 32-bit if a transparent layer is available
        if(!header_only && dib_alpha) {
            FIBITMAP *dst = FreeImage_ConvertTo32Bits(dib);
            if((FreeImage_GetBPP(dib_alpha) == 8) && (FreeImage_GetImageType(dib_alpha) == FIT_BITMAP)) {
                FreeImage_SetChannel(dst, dib_alpha, FICC_ALPHA);
            } else {
                FIBITMAP *dst_alpha = FreeImage_ConvertTo8Bits(dib_alpha);
                FreeImage_SetChannel(dst, dst_alpha, FICC_ALPHA);
                FreeImage_Unload(dst_alpha);
            }
            FreeImage_Unload(dib);
            dib = dst;
        }
        FreeImage_Unload(dib_alpha);

        if(dib) {
            // set metadata
            FreeImage_SetDotsPerMeterX(dib, res_x);
            FreeImage_SetDotsPerMeterY(dib, res_y);
            if(hasBkColor) {
                FreeImage_SetBackgroundColor(dib, &rgbBkColor);
            }
            if(key_value_pair.size()) {
                for(tEXtMAP::iterator j = key_value_pair.begin(); j != key_value_pair.end(); j++) {
                    std::string key = (*j).first;
                    std::string value = (*j).second;
                    mng_SetKeyValue(FIMD_COMMENTS, dib, key.c_str(), value.c_str());
                }
            }
        }

        return dib;

    } catch(const char *text) {
        FreeImage_CloseMemory(hJpegMemory);
        FreeImage_CloseMemory(hPngMemory);
        FreeImage_CloseMemory(hIDATMemory);
        free(mChunk);
        free(PLTE_file_chunk);
        FreeImage_Unload(dib);
        FreeImage_Unload(dib_alpha);
        if(text) {
            FreeImage_OutputMessageProc(format_id, text);
        }
        return NULL;
    }
}
Exemplo n.º 5
0
/**
   Count the number of bytes in a PNG stream, from IHDR to IEND.
   If successful, the stream position, as given by io->tell_proc(handle),
   should be the end of the PNG stream at the return of the function.
   @param io
   @param handle
   @param inPos
   @param m_TotalBytesOfChunks
   @return Returns TRUE if successful, returns FALSE otherwise
*/
static BOOL
mng_CountPNGChunks(FreeImageIO *io, fi_handle handle, long inPos, unsigned *m_TotalBytesOfChunks) {
    long mLOF;
    long mPos;
    BOOL mEnd = FALSE;
    DWORD mLength = 0;
    BYTE mChunkName[5];

    *m_TotalBytesOfChunks = 0;

    // get the length of the file
    mLOF = mng_LOF(io, handle);

    // go to the start of the file
    io->seek_proc(handle, inPos, SEEK_SET);

    try {
        // parse chunks
        while(mEnd == FALSE) {
            // chunk length
            mPos = io->tell_proc(handle);
            if(mPos + 4 > mLOF) {
                throw(1);
            }
            io->read_proc(&mLength, 1, 4, handle);
            mng_SwapLong(&mLength);
            // chunk name
            mPos = io->tell_proc(handle);
            if(mPos + 4 > mLOF) {
                throw(1);
            }
            io->read_proc(&mChunkName[0], 1, 4, handle);
            mChunkName[4] = '\0';

            // go to next chunk
            mPos = io->tell_proc(handle);
            // 4 = size of the CRC
            if(mPos + (long)mLength + 4 > mLOF) {
                throw(1);
            }
            io->seek_proc(handle, mLength + 4, SEEK_CUR);

            switch( mng_GetChunckType(mChunkName) ) {
                case IHDR:
                    if(mLength != 13) {
                        throw(1);
                    }
                    break;

                case IEND:
                    mEnd = TRUE;
                    // the length below includes 4 bytes CRC, but no bytes for Length
                    *m_TotalBytesOfChunks = io->tell_proc(handle) - inPos;
                    break;

                case UNKNOWN_CHUNCK:
                default:
                    break;
            }

        } // while(!mEnd)

        return TRUE;

    } catch(int) {
        return FALSE;
    }
}