/* * Copyright (c) 2007, Digital Signal Processing Laboratory, Università degli studi di Perugia (UPG), Italy * 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 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. */ ///////////////////////////////////////////////////////////////////////////// // Name: imagmj2.cpp // Purpose: wxImage Motion JPEG 2000 file format handler // Author: Giuseppe Baruffa - based on imagjpeg.cpp, Vaclav Slavik // RCS-ID: $Id: imagmj2.cpp,v 0.00 2007/02/18 23:59:00 MW Exp $ // Copyright: (c) Giuseppe Baruffa // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// // For compilers that support precompilation, includes "wx.h". #include "wx/wxprec.h" #ifdef __BORLANDC__ #pragma hdrstop #endif #if wxUSE_IMAGE && wxUSE_LIBOPENJPEG #include "imagmj2.h" #ifndef WX_PRECOMP #include "wx/log.h" #include "wx/app.h" #include "wx/intl.h" #include "wx/bitmap.h" #include "wx/module.h" #endif #include "libopenjpeg/openjpeg.h" #include "wx/filefn.h" #include "wx/wfstream.h" // ---------------------------------------------------------------------------- // types // ---------------------------------------------------------------------------- //----------------------------------------------------------------------------- // wxMJ2Handler //----------------------------------------------------------------------------- IMPLEMENT_DYNAMIC_CLASS(wxMJ2Handler,wxImageHandler) #if wxUSE_STREAMS //------------- JPEG 2000 Data Source Manager #define J2K_CFMT 0 #define JP2_CFMT 1 #define JPT_CFMT 2 #define MJ2_CFMT 3 #define PXM_DFMT 0 #define PGX_DFMT 1 #define BMP_DFMT 2 #define YUV_DFMT 3 #define MAX_MESSAGE_LEN 200 /* sample error callback expecting a FILE* client object */ void mj2_error_callback(const char *msg, void *client_data) { int message_len = strlen(msg) - 1; if (msg[message_len] != '\n') message_len = MAX_MESSAGE_LEN; wxMutexGuiEnter(); wxLogMessage(wxT("[ERROR] %.*s"), message_len, msg); wxMutexGuiLeave(); } /* sample warning callback expecting a FILE* client object */ void mj2_warning_callback(const char *msg, void *client_data) { int message_len = strlen(msg) - 1; if (msg[message_len] != '\n') message_len = MAX_MESSAGE_LEN; wxMutexGuiEnter(); wxLogMessage(wxT("[WARNING] %.*s"), message_len, msg); wxMutexGuiLeave(); } /* sample debug callback expecting no client object */ void mj2_info_callback(const char *msg, void *client_data) { int message_len = strlen(msg) - 1; if (msg[message_len] != '\n') message_len = MAX_MESSAGE_LEN; wxMutexGuiEnter(); wxLogMessage(wxT("[INFO] %.*s"), message_len, msg); wxMutexGuiLeave(); } /* macro functions */ /* From little endian to big endian, 2 and 4 bytes */ #define BYTE_SWAP2(X) ((X & 0x00FF) << 8) | ((X & 0xFF00) >> 8) #define BYTE_SWAP4(X) ((X & 0x000000FF) << 24) | ((X & 0x0000FF00) << 8) | ((X & 0x00FF0000) >> 8) | ((X & 0xFF000000) >> 24) #define BYTE_SWAP8(X) ((X & 0x00000000000000FF) << 56) | ((X & 0x000000000000FF00) << 40) | \ ((X & 0x0000000000FF0000) << 24) | ((X & 0x00000000FF000000) << 8) | \ ((X & 0x000000FF00000000) >> 8) | ((X & 0x0000FF0000000000) >> 24) | \ ((X & 0x00FF000000000000) >> 40) | ((X & 0xFF00000000000000) >> 56) /* From codestream to int values */ #define STREAM_TO_UINT32(C, P) (((unsigned long int) (C)[(P) + 0] << 24) + \ ((unsigned long int) (C)[(P) + 1] << 16) + \ ((unsigned long int) (C)[(P) + 2] << 8) + \ ((unsigned long int) (C)[(P) + 3] << 0)) #define STREAM_TO_UINT16(C, P) (((unsigned long int) (C)[(P) + 0] << 8) + \ ((unsigned long int) (C)[(P) + 1] << 0)) /* defines */ #define SHORT_DESCR_LEN 32 #define LONG_DESCR_LEN 256 /* enumeration for file formats */ #define J2FILENUM 4 typedef enum { JP2_FILE, J2K_FILE, MJ2_FILE, UNK_FILE } my_j2filetype; /* enumeration for the box types */ #define J2BOXNUM 23 typedef enum { FILE_BOX, JP_BOX, FTYP_BOX, JP2H_BOX, IHDR_BOX, COLR_BOX, JP2C_BOX, JP2I_BOX, XML_BOX, UUID_BOX, UINF_BOX, MOOV_BOX, MVHD_BOX, TRAK_BOX, TKHD_BOX, MDIA_BOX, MINF_BOX, STBL_BOX, STSD_BOX, MJP2_BOX, MDAT_BOX, ANY_BOX, UNK_BOX } my_j2boxtype; /* jp2 family box signatures */ #define FILE_SIGN "" #define JP_SIGN "jP\040\040" #define FTYP_SIGN "ftyp" #define JP2H_SIGN "jp2h" #define IHDR_SIGN "ihdr" #define COLR_SIGN "colr" #define JP2C_SIGN "jp2c" #define JP2I_SIGN "jp2i" #define XML_SIGN "xml\040" #define UUID_SIGN "uuid" #define UINF_SIGN "uinf" #define MOOV_SIGN "moov" #define MVHD_SIGN "mvhd" #define TRAK_SIGN "trak" #define TKHD_SIGN "tkhd" #define MDIA_SIGN "mdia" #define MINF_SIGN "minf" #define VMHD_SIGN "vmhd" #define STBL_SIGN "stbl" #define STSD_SIGN "stsd" #define MJP2_SIGN "mjp2" #define MDAT_SIGN "mdat" #define ANY_SIGN "" #define UNK_SIGN "" /* the box structure itself */ struct my_boxdef { char value[5]; /* hexadecimal value/string*/ char name[SHORT_DESCR_LEN]; /* short description */ char descr[LONG_DESCR_LEN]; /* long description */ int sbox; /* is it a superbox? */ int req[J2FILENUM]; /* mandatory box */ my_j2boxtype ins; /* contained in box... */ }; /* the possible boxes */ struct my_boxdef j2box[] = { /* sign */ {FILE_SIGN, /* short */ "placeholder for nothing", /* long */ "Nothing to say", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {JP_SIGN, /* short */ "JPEG 2000 Signature box", /* long */ "This box uniquely identifies the file as being part of the JPEG 2000 family of files", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {FTYP_SIGN, /* short */ "File Type box", /* long */ "This box specifies file type, version and compatibility information, including specifying if this file " "is a conforming JP2 file or if it can be read by a conforming JP2 reader", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {JP2H_SIGN, /* short */ "JP2 Header box", /* long */ "This box contains a series of boxes that contain header-type information about the file", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {IHDR_SIGN, /* short */ "Image Header box", /* long */ "This box specifies the size of the image and other related fields", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ JP2H_BOX}, /* sign */ {COLR_SIGN, /* short */ "Colour Specification box", /* long */ "This box specifies the colourspace of the image", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ JP2H_BOX}, /* sign */ {JP2C_SIGN, /* short */ "Contiguous Codestream box", /* long */ "This box contains the codestream as defined by Annex A", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {JP2I_SIGN, /* short */ "Intellectual Property box", /* long */ "This box contains intellectual property information about the image", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ FILE_BOX}, /* sign */ {XML_SIGN, /* short */ "XML box", /* long */ "This box provides a tool by which vendors can add XML formatted information to a JP2 file", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ FILE_BOX}, /* sign */ {UUID_SIGN, /* short */ "UUID box", /* long */ "This box provides a tool by which vendors can add additional information to a file " "without risking conflict with other vendors", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ FILE_BOX}, /* sign */ {UINF_SIGN, /* short */ "UUID Info box", /* long */ "This box provides a tool by which a vendor may provide access to additional information associated with a UUID", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ FILE_BOX}, /* sign */ {MOOV_SIGN, /* short */ "Movie box", /* long */ "This box contains the media data. In video tracks, this box would contain JPEG2000 video frames", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {MVHD_SIGN, /* short */ "Movie Header box", /* long */ "This box defines overall information which is media-independent, and relevant to the entire presentation " "considered as a whole", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ MOOV_BOX}, /* sign */ {TRAK_SIGN, /* short */ "Track box", /* long */ "This is a container box for a single track of a presentation. A presentation may consist of one or more tracks", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ MOOV_BOX}, /* sign */ {TKHD_SIGN, /* short */ "Track Header box", /* long */ "This box specifies the characteristics of a single track. Exactly one Track Header Box is contained in a track", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ TRAK_BOX}, /* sign */ {MDIA_SIGN, /* short */ "Media box", /* long */ "The media declaration container contains all the objects which declare information about the media data " "within a track", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ TRAK_BOX}, /* sign */ {MINF_SIGN, /* short */ "Media Information box", /* long */ "This box contains all the objects which declare characteristic information of the media in the track", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ MDIA_BOX}, /* sign */ {STBL_SIGN, /* short */ "Sample Table box", /* long */ "The sample table contains all the time and data indexing of the media samples in a track", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ MINF_BOX}, /* sign */ {STSD_SIGN, /* short */ "Sample Description box", /* long */ "The sample description table gives detailed information about the coding type used, and any initialization " "information needed for that coding", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ MINF_BOX}, /* sign */ {MJP2_SIGN, /* short */ "MJP2 Sample Description box", /* long */ "The MJP2 sample description table gives detailed information about the coding type used, and any initialization " "information needed for that coding", /* sbox */ 0, /* req */ {1, 1, 1}, /* ins */ MINF_BOX}, /* sign */ {MDAT_SIGN, /* short */ "Media Data box", /* long */ "The meta-data for a presentation is stored in the single Movie Box which occurs at the top-level of a file", /* sbox */ 1, /* req */ {1, 1, 1}, /* ins */ FILE_BOX}, /* sign */ {ANY_SIGN, /* short */ "Any box", /* long */ "All the existing boxes", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ FILE_BOX}, /* sign */ {UNK_SIGN, /* short */ "Unknown Type box", /* long */ "The signature is not recognised to be that of an existing box", /* sbox */ 0, /* req */ {0, 0, 0}, /* ins */ ANY_BOX} }; /* declaration */ int my_box_handler_function(my_j2boxtype boxtype, wxInputStream& stream, unsigned long int filepoint, unsigned long int filelimit, int level, char *scansign, unsigned long int *scanpoint); #ifdef __WXMSW__ typedef unsigned __int64 int8byte; #endif // __WXMSW__ #ifdef __WXGTK__ typedef unsigned long long int8byte; #endif // __WXGTK__ /* internal mini-search for a box signature */ int my_jpeg2000parse(wxInputStream& stream, unsigned long int filepoint, unsigned long int filelimit, int level, char *scansign, unsigned long int *scanpoint) { unsigned long int LBox = 0x00000000; //int LBox_read; char TBox[5] = "\0\0\0\0"; //int TBox_read; int8byte XLBox = 0x0000000000000000; //int XLBox_read; unsigned long int box_length = 0; int last_box = 0, box_num = 0; int box_type = ANY_BOX; unsigned char /*onebyte[1], twobytes[2],*/ fourbytes[4]; int box_number = 0; /* cycle all over the file */ box_num = 0; last_box = 0; while (!last_box) { /* do not exceed file limit */ if (filepoint >= filelimit) return (0); /* seek on file */ if (stream.SeekI(filepoint, wxFromStart) == wxInvalidOffset) return (-1); /* read the mandatory LBox, 4 bytes */ if (!stream.Read(fourbytes, 4)) { (wxT("Problem reading LBox from the file (file ended?)")); return -1; }; LBox = STREAM_TO_UINT32(fourbytes, 0); /* read the mandatory TBox, 4 bytes */ if (!stream.Read(TBox, 4)) { wxLogError(wxT("Problem reading TBox from the file (file ended?)")); return -1; }; /* look if scansign is got */ if ((scansign != NULL) && (memcmp(TBox, scansign, 4) == 0)) { /* hack/exploit */ // stop as soon as you find the level-th codebox if (box_number == level) { memcpy(scansign, " ", 4); *scanpoint = filepoint; return (0); } else box_number++; }; /* determine the box type */ for (box_type = JP_BOX; box_type < UNK_BOX; box_type++) if (memcmp(TBox, j2box[box_type].value, 4) == 0) break; /* read the optional XLBox, 8 bytes */ if (LBox == 1) { if (!stream.Read(&XLBox, 8)) { wxLogError(wxT("Problem reading XLBox from the file (file ended?)")); return -1; }; box_length = (unsigned long int) BYTE_SWAP8(XLBox); } else if (LBox == 0x00000000) { /* last box in file */ last_box = 1; box_length = filelimit - filepoint; } else box_length = LBox; /* go deep in the box */ my_box_handler_function((my_j2boxtype) box_type, stream, (LBox == 1) ? (filepoint + 16) : (filepoint + 8), filepoint + box_length, level, scansign, scanpoint); /* if it's a superbox go inside it */ if (j2box[box_type].sbox) my_jpeg2000parse(stream, (LBox == 1) ? (filepoint + 16) : (filepoint + 8), filepoint + box_length, level, scansign, scanpoint); /* increment box number and filepoint*/ box_num++; filepoint += box_length; }; /* all good */ return (0); } // search first contiguos codestream box in an mj2 file unsigned long int searchjp2c(wxInputStream& stream, unsigned long int fsize, int number) { char scansign[] = "jp2c"; unsigned long int scanpoint = 0L; wxLogMessage(wxT("MJ2: searching jp2c box... ")); /* do the parsing */ if (my_jpeg2000parse(stream, 0, fsize, number, scansign, &scanpoint) < 0) wxLogMessage(wxT("MJ2: Unrecoverable error during file parsing: stopping")); if (strcmp(scansign, " ")) wxLogMessage(wxT("MJ2: not found")); else { wxLogMessage(wxString::Format(wxT("MJ2: found at byte %d"), scanpoint)); }; return (scanpoint); } // search the jp2h box in the file unsigned long int searchjpegheaderbox(wxInputStream& stream, unsigned long int fsize) { char scansign[] = "jp2h"; unsigned long int scanpoint = 0L; wxLogMessage(wxT("MJ2: searching jp2h box... ")); /* do the parsing */ if (my_jpeg2000parse(stream, 0, fsize, 0, scansign, &scanpoint) < 0) wxLogMessage(wxT("Unrecoverable error during file parsing: stopping")); if (strcmp(scansign, " ")) wxLogMessage(wxT("MJ2: not found")); else wxLogMessage(wxString::Format(wxT("MJ2: found at byte %d"), scanpoint)); return (scanpoint); } /* handling functions */ #define ITEM_PER_ROW 10 /* Box handler function */ int my_box_handler_function(my_j2boxtype boxtype, wxInputStream& stream, unsigned long int filepoint, unsigned long int filelimit, int level, char *scansign, unsigned long int *scanpoint) { switch (boxtype) { /* Sample Description box */ case (STSD_BOX): my_jpeg2000parse(stream, filepoint + 8, filelimit, level, scansign, scanpoint); break; /* MJP2 Sample Description box */ case (MJP2_BOX): my_jpeg2000parse(stream, filepoint + 78, filelimit, level, scansign, scanpoint); break; /* not yet implemented */ default: break; }; return (0); } // the jP and ftyp parts of the header #define my_jPheadSIZE 32 unsigned char my_jPhead[my_jPheadSIZE] = { 0x00, 0x00, 0x00, 0x0C, 'j', 'P', ' ', ' ', 0x0D, 0x0A, 0x87, 0x0A, 0x00, 0x00, 0x00, 0x14, 'f', 't', 'y', 'p', 'j', 'p', '2', ' ', 0x00, 0x00, 0x00, 0x00, 'j', 'p', '2', ' ' }; ///////////////////////////////////////////////// ///////////////////////////////////////////////// // load the mj2 file format bool wxMJ2Handler::LoadFile(wxImage *image, wxInputStream& stream, bool verbose, int index) { opj_dparameters_t parameters; /* decompression parameters */ opj_event_mgr_t event_mgr; /* event manager */ opj_image_t *opjimage = NULL; unsigned char *src = NULL; unsigned char *ptr; int file_length, jp2c_point, jp2h_point; unsigned long int jp2hboxlen, jp2cboxlen; // destroy the image image->Destroy(); /* handle to a decompressor */ opj_dinfo_t* dinfo = NULL; opj_cio_t *cio = NULL; /* configure the event callbacks (not required) */ memset(&event_mgr, 0, sizeof(opj_event_mgr_t)); event_mgr.error_handler = mj2_error_callback; event_mgr.warning_handler = mj2_warning_callback; event_mgr.info_handler = mj2_info_callback; /* set decoding parameters to default values */ opj_set_default_decoder_parameters(¶meters); /* prepare parameters */ strncpy(parameters.infile, "", sizeof(parameters.infile)-1); strncpy(parameters.outfile, "", sizeof(parameters.outfile)-1); parameters.decod_format = JP2_CFMT; parameters.cod_format = BMP_DFMT; if (m_reducefactor) parameters.cp_reduce = m_reducefactor; if (m_qualitylayers) parameters.cp_layer = m_qualitylayers; /*if (n_components) parameters. = n_components;*/ /* JPWL only */ #ifdef USE_JPWL parameters.jpwl_exp_comps = m_expcomps; parameters.jpwl_max_tiles = m_maxtiles; parameters.jpwl_correct = m_enablejpwl; #endif /* USE_JPWL */ /* get a decoder handle */ dinfo = opj_create_decompress(CODEC_JP2); /* find length of the stream */ stream.SeekI(0, wxFromEnd); file_length = (int) stream.TellI(); /* search for the first codestream box and the movie header box */ jp2c_point = searchjp2c(stream, file_length, m_framenum); jp2h_point = searchjpegheaderbox(stream, file_length); // read the jp2h box and store it stream.SeekI(jp2h_point, wxFromStart); stream.Read(&jp2hboxlen, sizeof(unsigned long int)); jp2hboxlen = BYTE_SWAP4(jp2hboxlen); // read the jp2c box and store it stream.SeekI(jp2c_point, wxFromStart); stream.Read(&jp2cboxlen, sizeof(unsigned long int)); jp2cboxlen = BYTE_SWAP4(jp2cboxlen); // malloc memory source src = (unsigned char *) malloc(my_jPheadSIZE + jp2hboxlen + jp2cboxlen); // copy the jP and ftyp memcpy(src, my_jPhead, my_jPheadSIZE); // copy the jp2h stream.SeekI(jp2h_point, wxFromStart); stream.Read(&src[my_jPheadSIZE], jp2hboxlen); // copy the jp2c stream.SeekI(jp2c_point, wxFromStart); stream.Read(&src[my_jPheadSIZE + jp2hboxlen], jp2cboxlen); /* catch events using our callbacks and give a local context */ opj_set_event_mgr((opj_common_ptr)dinfo, &event_mgr, stderr); /* setup the decoder decoding parameters using user parameters */ opj_setup_decoder(dinfo, ¶meters); /* open a byte stream */ cio = opj_cio_open((opj_common_ptr)dinfo, src, my_jPheadSIZE + jp2hboxlen + jp2cboxlen); /* decode the stream and fill the image structure */ opjimage = opj_decode(dinfo, cio); if (!opjimage) { wxMutexGuiEnter(); wxLogError(wxT("MJ2: failed to decode image!")); wxMutexGuiLeave(); opj_destroy_decompress(dinfo); opj_cio_close(cio); free(src); return false; } /* close the byte stream */ opj_cio_close(cio); // check image size if ((opjimage->numcomps != 1) && (opjimage->numcomps != 3)) { wxMutexGuiEnter(); wxLogError(wxT("MJ2: weird number of components")); wxMutexGuiLeave(); opj_destroy_decompress(dinfo); free(src); return false; } // prepare image size image->Create(opjimage->comps[0].w, opjimage->comps[0].h, true ); // access image raw data image->SetMask( false ); ptr = image->GetData(); // RGB color picture // does not handle comps. subsampling, // so simply render the first component if (opjimage->numcomps == 3) { int row, col; int *r = opjimage->comps[0].data; /* int *g = opjimage->comps[1].data; int *b = opjimage->comps[2].data; */ for (row = 0; row < opjimage->comps[0].h; row++) { for (col = 0; col < opjimage->comps[0].w; col++) { /* *(ptr++) = *(r++); *(ptr++) = *(g++); *(ptr++) = *(b++); */ *(ptr++) = *(r); *(ptr++) = *(r); *(ptr++) = *(r++); } } } // B/W picture if (opjimage->numcomps == 1) { int row, col; int *y = opjimage->comps[0].data; for (row = 0; row < opjimage->comps[0].h; row++) { for (col = 0; col < opjimage->comps[0].w; col++) { *(ptr++) = *(y); *(ptr++) = *(y); *(ptr++) = *(y++); } } } wxMutexGuiEnter(); wxLogMessage(wxT("MJ2: image loaded.")); wxMutexGuiLeave(); /* close openjpeg structs */ opj_destroy_decompress(dinfo); opj_image_destroy(opjimage); free(src); if (!image->Ok()) return false; else return true; } // save the mj2 file format bool wxMJ2Handler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose ) { wxLogError(wxT("MJ2: Couldn't save movie -> not implemented.")); return false; } #ifdef __VISUALC__ #pragma warning(default:4611) #endif /* VC++ */ // recognize the Motion JPEG 2000 starting box bool wxMJ2Handler::DoCanRead( wxInputStream& stream ) { unsigned char hdr[24]; if ( !stream.Read(hdr, WXSIZEOF(hdr)) ) return false; return (hdr[0] == 0x00 && hdr[1] == 0x00 && hdr[2] == 0x00 && hdr[3] == 0x0C && hdr[4] == 0x6A && hdr[5] == 0x50 && hdr[6] == 0x20 && hdr[7] == 0x20 && hdr[20] == 0x6D && hdr[21] == 0x6A && hdr[22] == 0x70 && hdr[23] == 0x32); } #endif // wxUSE_STREAMS #endif // wxUSE_LIBOPENJPEG