text: /* public domain Simple, Minimalistic JPEG writer - http://jonolick.com
   *
   * Quick Notes:
   * 	Based on a javascript jpeg writer
   * 	JPEG baseline (no JPEG progressive)
   * 	Supports 1, 3 or 4 component input. (luminance, RGB or RGBX)
   *
   * Latest revisions:
   *	1.53 (2016-07-08) Added support to compile as plain C code.
   *	1.52 (2012-22-11) Added support for specifying Luminance, RGB, or RGBA via comp(onents) argument (1, 3 and 4 respectively). 
   *	1.51 (2012-19-11) Fixed some warnings
   *	1.50 (2012-18-11) MT safe. Simplified. Optimized. Reduced memory requirements. Zero allocations. No namespace polution. Approx 340 lines code.
   *	1.10 (2012-16-11) compile fixes, added docs,
   *		changed from .h to .cpp (simpler to bootstrap), etc
   * 	1.00 (2012-02-02) initial release
   *
   * Basic usage:
   *	char *foo = new char[128*128*4]; // 4 component. RGBX format, where X is unused 
   *	jo_write_jpg("foo.jpg", foo, 128, 128, 4, 90); // comp can be 1, 3, or 4. Lum, RGB, or RGBX respectively.
   * 	
   * */
  
  #ifndef JO_INCLUDE_JPEG_H
  #define JO_INCLUDE_JPEG_H
  
  // To get a header file for this, either cut and paste the header,
  // or create jo_jpeg.h, #define JO_JPEG_HEADER_FILE_ONLY, and
  // then include jo_jpeg.c from it.
  
  // Returns false on failure
  extern int jo_write_jpg(const char *filename, const void *data, int width, int height, int comp, int quality);
  
  #endif // JO_INCLUDE_JPEG_H
  
  #ifndef JO_JPEG_HEADER_FILE_ONLY
  
  #if defined(_MSC_VER) && _MSC_VER >= 0x1400
  #define _CRT_SECURE_NO_WARNINGS // suppress warnings about fopen()
  #endif
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <math.h>
  
  static const unsigned char s_jo_ZigZag[] = { 0,1,5,6,14,15,27,28,2,4,7,13,16,26,29,42,3,8,12,17,25,30,41,43,9,11,18,24,31,40,44,53,10,19,23,32,39,45,52,54,20,22,33,38,46,51,55,60,21,34,37,47,50,56,59,61,35,36,48,49,57,58,62,63 };
  
  static void jo_writeBits(FILE *fp, int *bitBuf, int *bitCnt, const unsigned short *bs) {
  	*bitCnt += bs[1];
  	*bitBuf |= bs[0] << (24 - *bitCnt);
  	while(*bitCnt >= 8) {
  		unsigned char c = (*bitBuf >> 16) & 255;
  		putc(c, fp);
  		if(c == 255) {
  			putc(0, fp);
  		}
  		*bitBuf <<= 8;
  		*bitCnt -= 8;
  	}
  }
  
  static void jo_DCT(float *d0, float *d1, float *d2, float *d3, float *d4, float *d5, float *d6, float *d7) {
  	float tmp0 = *d0 + *d7;
  	float tmp7 = *d0 - *d7;
  	float tmp1 = *d1 + *d6;
  	float tmp6 = *d1 - *d6;
  	float tmp2 = *d2 + *d5;
  	float tmp5 = *d2 - *d5;
  	float tmp3 = *d3 + *d4;
  	float tmp4 = *d3 - *d4;
  
  	// Even part
  	float tmp10 = tmp0 + tmp3;	// phase 2
  	float tmp13 = tmp0 - tmp3;
  	float tmp11 = tmp1 + tmp2;
  	float tmp12 = tmp1 - tmp2;
  
  	*d0 = tmp10 + tmp11; 		// phase 3
  	*d4 = tmp10 - tmp11;
  
  	float z1 = (tmp12 + tmp13) * 0.707106781f; // c4
  	*d2 = tmp13 + z1; 		// phase 5
  	*d6 = tmp13 - z1;
  
  	// Odd part
  	tmp10 = tmp4 + tmp5; 		// phase 2
  	tmp11 = tmp5 + tmp6;
  	tmp12 = tmp6 + tmp7;
  
  	// The rotator is modified from fig 4-8 to avoid extra negations.
  	float z5 = (tmp10 - tmp12) * 0.382683433f; // c6
  	float z2 = tmp10 * 0.541196100f + z5; // c2-c6
  	float z4 = tmp12 * 1.306562965f + z5; // c2+c6
  	float z3 = tmp11 * 0.707106781f; // c4
  
  	float z11 = tmp7 + z3;		// phase 5
  	float z13 = tmp7 - z3;
  
  	*d5 = z13 + z2;			// phase 6
  	*d3 = z13 - z2;
  	*d1 = z11 + z4;
  	*d7 = z11 - z4;
  } 
  
  static void jo_calcBits(int val, unsigned short bits[2]) {
  	int tmp1 = val < 0 ? -val : val;
  	val = val < 0 ? val-1 : val;
  	bits[1] = 1;
  	while(tmp1 >>= 1) {
  		++bits[1];
  	}
  	bits[0] = val & ((1<<bits[1])-1);
  }
  
  static int jo_processDU(FILE *fp, int *bitBuf, int *bitCnt, float *CDU, float *fdtbl, int DC, const unsigned short HTDC[256][2], const unsigned short HTAC[256][2]) {
  	const unsigned short EOB[2] = { HTAC[0x00][0], HTAC[0x00][1] };
  	const unsigned short M16zeroes[2] = { HTAC[0xF0][0], HTAC[0xF0][1] };
  	int dataOff, i, nrmarker;
  	
  	// DCT rows
  	for(dataOff=0; dataOff<64; dataOff+=8) {
  		jo_DCT(&CDU[dataOff], &CDU[dataOff+1], &CDU[dataOff+2], &CDU[dataOff+3], &CDU[dataOff+4], &CDU[dataOff+5], &CDU[dataOff+6], &CDU[dataOff+7]);
  	}
  	// DCT columns
  	for(dataOff=0; dataOff<8; ++dataOff) {
  		jo_DCT(&CDU[dataOff], &CDU[dataOff+8], &CDU[dataOff+16], &CDU[dataOff+24], &CDU[dataOff+32], &CDU[dataOff+40], &CDU[dataOff+48], &CDU[dataOff+56]);
  	}
  	// Quantize/descale/zigzag the coefficients
  	int DU[64];
  	for(i=0; i<64; ++i) {
  		float v = CDU[i]*fdtbl[i];
  		DU[s_jo_ZigZag[i]] = (int)(v < 0 ? ceilf(v - 0.5f) : floorf(v + 0.5f));
  	}
  
  	// Encode DC
  	int diff = DU[0] - DC; 
  	if (diff == 0) {
  		jo_writeBits(fp, bitBuf, bitCnt, HTDC[0]);
  	} else {
  		unsigned short bits[2];
  		jo_calcBits(diff, bits);
  		jo_writeBits(fp, bitBuf, bitCnt, HTDC[bits[1]]);
  		jo_writeBits(fp, bitBuf, bitCnt, bits);
  	}
  	// Encode ACs
  	int end0pos = 63;
  	for(; (end0pos>0)&&(DU[end0pos]==0); --end0pos) {
  	}
  	// end0pos = first element in reverse order !=0
  	if(end0pos == 0) {
  		jo_writeBits(fp, bitBuf, bitCnt, EOB);
  		return DU[0];
  	}
  	for(i = 1; i <= end0pos; ++i) {
  		int startpos = i;
  		for (; DU[i]==0 && i<=end0pos; ++i) {
  		}
  		int nrzeroes = i-startpos;
  		if ( nrzeroes >= 16 ) {
  			int lng = nrzeroes>>4;
  			for (nrmarker=1; nrmarker <= lng; ++nrmarker)
  				jo_writeBits(fp, bitBuf, bitCnt, M16zeroes);
  			nrzeroes &= 15;
  		}
  		unsigned short bits[2];
  		jo_calcBits(DU[i], bits);
  		jo_writeBits(fp, bitBuf, bitCnt, HTAC[(nrzeroes<<4)+bits[1]]);
  		jo_writeBits(fp, bitBuf, bitCnt, bits);
  	}
  	if(end0pos != 63) {
  		jo_writeBits(fp, bitBuf, bitCnt, EOB);
  	}
  	return DU[0];
  }
  
  int jo_write_jpg(const char *filename, const void *data, int width, int height, int comp, int quality) {
  	// Constants that don't pollute global namespace
  	static const unsigned char std_dc_luminance_nrcodes[] = {0,0,1,5,1,1,1,1,1,1,0,0,0,0,0,0,0};
  	static const unsigned char std_dc_luminance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
  	static const unsigned char std_ac_luminance_nrcodes[] = {0,0,2,1,3,3,2,4,3,5,5,4,4,0,0,1,0x7d};
  	static const unsigned char std_ac_luminance_values[] = {
  		0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08,
  		0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28,
  		0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59,
  		0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89,
  		0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6,
  		0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2,
  		0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
  	};
  	static const unsigned char std_dc_chrominance_nrcodes[] = {0,0,3,1,1,1,1,1,1,1,1,1,0,0,0,0,0};
  	static const unsigned char std_dc_chrominance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
  	static const unsigned char std_ac_chrominance_nrcodes[] = {0,0,2,1,2,4,4,3,4,7,5,4,4,0,1,2,0x77};
  	static const unsigned char std_ac_chrominance_values[] = {
  		0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91,
  		0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26,
  		0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,
  		0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87,
  		0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,
  		0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,
  		0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
  	};
  	// Huffman tables
  	static const unsigned short YDC_HT[256][2] = { {0,2},{2,3},{3,3},{4,3},{5,3},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9}};
  	static const unsigned short UVDC_HT[256][2] = { {0,2},{1,2},{2,2},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9},{1022,10},{2046,11}};
  	static const unsigned short YAC_HT[256][2] = { 
  		{10,4},{0,2},{1,2},{4,3},{11,4},{26,5},{120,7},{248,8},{1014,10},{65410,16},{65411,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{12,4},{27,5},{121,7},{502,9},{2038,11},{65412,16},{65413,16},{65414,16},{65415,16},{65416,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{28,5},{249,8},{1015,10},{4084,12},{65417,16},{65418,16},{65419,16},{65420,16},{65421,16},{65422,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{58,6},{503,9},{4085,12},{65423,16},{65424,16},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{59,6},{1016,10},{65430,16},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{122,7},{2039,11},{65438,16},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{123,7},{4086,12},{65446,16},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{250,8},{4087,12},{65454,16},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{504,9},{32704,15},{65462,16},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{505,9},{65470,16},{65471,16},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{506,9},{65479,16},{65480,16},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{1017,10},{65488,16},{65489,16},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{1018,10},{65497,16},{65498,16},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{2040,11},{65506,16},{65507,16},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{65515,16},{65516,16},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{2041,11},{65525,16},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0}
  	};
  	static const unsigned short UVAC_HT[256][2] = { 
  		{0,2},{1,2},{4,3},{10,4},{24,5},{25,5},{56,6},{120,7},{500,9},{1014,10},{4084,12},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{11,4},{57,6},{246,8},{501,9},{2038,11},{4085,12},{65416,16},{65417,16},{65418,16},{65419,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{26,5},{247,8},{1015,10},{4086,12},{32706,15},{65420,16},{65421,16},{65422,16},{65423,16},{65424,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{27,5},{248,8},{1016,10},{4087,12},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{65430,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{58,6},{502,9},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{65438,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{59,6},{1017,10},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{65446,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{121,7},{2039,11},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{65454,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{122,7},{2040,11},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{65462,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{249,8},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{65470,16},{65471,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{503,9},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{65479,16},{65480,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{504,9},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{65488,16},{65489,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{505,9},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{65497,16},{65498,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{506,9},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{65506,16},{65507,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{2041,11},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{65515,16},{65516,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{16352,14},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{65525,16},{0,0},{0,0},{0,0},{0,0},{0,0},
  		{1018,10},{32707,15},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0}
  	};
  	static const int YQT[] = {16,11,10,16,24,40,51,61,12,12,14,19,26,58,60,55,14,13,16,24,40,57,69,56,14,17,22,29,51,87,80,62,18,22,37,56,68,109,103,77,24,35,55,64,81,104,113,92,49,64,78,87,103,121,120,101,72,92,95,98,112,100,103,99};
  	static const int UVQT[] = {17,18,24,47,99,99,99,99,18,21,26,66,99,99,99,99,24,26,56,99,99,99,99,99,47,66,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99};
  	static const float aasf[] = { 1.0f * 2.828427125f, 1.387039845f * 2.828427125f, 1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f, 1.0f * 2.828427125f, 0.785694958f * 2.828427125f, 0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f };
  	int i, row, col, x, y, k, pos;
  	
  	if(!data || !filename || !width || !height || comp > 4 || comp < 1 || comp == 2) {
  		return 0;
  	}
  
  	FILE *fp = fopen(filename, "wb");
  	if(!fp) {
  		return 0;
  	}
  
  	quality = quality ? quality : 90;
  	quality = quality < 1 ? 1 : quality > 100 ? 100 : quality;
  	quality = quality < 50 ? 5000 / quality : 200 - quality * 2;
  
  	unsigned char YTable[64], UVTable[64];
  	for(i = 0; i < 64; ++i) {
  		int yti = (YQT[i]*quality+50)/100;
  		YTable[s_jo_ZigZag[i]] = yti < 1 ? 1 : yti > 255 ? 255 : yti;
  		int uvti  = (UVQT[i]*quality+50)/100;
  		UVTable[s_jo_ZigZag[i]] = uvti < 1 ? 1 : uvti > 255 ? 255 : uvti;
  	}
  
  	float fdtbl_Y[64], fdtbl_UV[64];
  	for(row = 0, k = 0; row < 8; ++row) {
  		for(col = 0; col < 8; ++col, ++k) {
  			fdtbl_Y[k]  = 1 / (YTable [s_jo_ZigZag[k]] * aasf[row] * aasf[col]);
  			fdtbl_UV[k] = 1 / (UVTable[s_jo_ZigZag[k]] * aasf[row] * aasf[col]);
  		}
  	}
  
  	// Write Headers
  	static const unsigned char head0[] = { 0xFF,0xD8,0xFF,0xE0,0,0x10,'J','F','I','F',0,1,1,0,0,1,0,1,0,0,0xFF,0xDB,0,0x84,0 };
  	fwrite(head0, sizeof(head0), 1, fp);
  	fwrite(YTable, sizeof(YTable), 1, fp);
  	putc(1, fp);
  	fwrite(UVTable, sizeof(UVTable), 1, fp);
  	const unsigned char head1[] = { 0xFF,0xC0,0,0x11,8,(unsigned char)(height>>8),(unsigned char)(height&0xFF),(unsigned char)(width>>8),(unsigned char)(width&0xFF),3,1,0x11,0,2,0x11,1,3,0x11,1,0xFF,0xC4,0x01,0xA2,0 };
  	fwrite(head1, sizeof(head1), 1, fp);
  	fwrite(std_dc_luminance_nrcodes+1, sizeof(std_dc_luminance_nrcodes)-1, 1, fp);
  	fwrite(std_dc_luminance_values, sizeof(std_dc_luminance_values), 1, fp);
  	putc(0x10, fp); // HTYACinfo
  	fwrite(std_ac_luminance_nrcodes+1, sizeof(std_ac_luminance_nrcodes)-1, 1, fp);
  	fwrite(std_ac_luminance_values, sizeof(std_ac_luminance_values), 1, fp);
  	putc(1, fp); // HTUDCinfo
  	fwrite(std_dc_chrominance_nrcodes+1, sizeof(std_dc_chrominance_nrcodes)-1, 1, fp);
  	fwrite(std_dc_chrominance_values, sizeof(std_dc_chrominance_values), 1, fp);
  	putc(0x11, fp); // HTUACinfo
  	fwrite(std_ac_chrominance_nrcodes+1, sizeof(std_ac_chrominance_nrcodes)-1, 1, fp);
  	fwrite(std_ac_chrominance_values, sizeof(std_ac_chrominance_values), 1, fp);
  	static const unsigned char head2[] = { 0xFF,0xDA,0,0xC,3,1,0,2,0x11,3,0x11,0,0x3F,0 };
  	fwrite(head2, sizeof(head2), 1, fp);
  
  	// Encode 8x8 macroblocks
  	const unsigned char *imageData = (const unsigned char *)data;
  	int DCY=0, DCU=0, DCV=0;
  	int bitBuf=0, bitCnt=0;
  	int ofsG = comp > 1 ? 1 : 0, ofsB = comp > 1 ? 2 : 0;
  	for(y = 0; y < height; y += 8) {
  		for(x = 0; x < width; x += 8) {
  			float YDU[64], UDU[64], VDU[64];
  			for(row = y, pos = 0; row < y+8; ++row) {
  				for(col = x; col < x+8; ++col, ++pos) {
  					int p = row*width*comp + col*comp;
  					if(row >= height) {
  						p -= width*comp*(row+1 - height);
  					}
  					if(col >= width) {
  						p -= comp*(col+1 - width);
  					}
  
  					float r = imageData[p+0], g = imageData[p+ofsG], b = imageData[p+ofsB];
  					YDU[pos]=+0.29900f*r+0.58700f*g+0.11400f*b-128;
  					UDU[pos]=-0.16874f*r-0.33126f*g+0.50000f*b;
  					VDU[pos]=+0.50000f*r-0.41869f*g-0.08131f*b;
  				}
  			}
  
  			DCY = jo_processDU(fp, &bitBuf, &bitCnt, YDU, fdtbl_Y, DCY, YDC_HT, YAC_HT);
  			DCU = jo_processDU(fp, &bitBuf, &bitCnt, UDU, fdtbl_UV, DCU, UVDC_HT, UVAC_HT);
  			DCV = jo_processDU(fp, &bitBuf, &bitCnt, VDU, fdtbl_UV, DCV, UVDC_HT, UVAC_HT);
  		}
  	}
  	
  	// Do the bit alignment of the EOI marker
  	static const unsigned short fillBits[] = {0x7F, 7};
  	jo_writeBits(fp, &bitBuf, &bitCnt, fillBits);
  
  	// EOI
  	putc(0xFF, fp);
  	putc(0xD9, fp);
  
  	fclose(fp);
  	return 1;
  }
  
  #endif
  
  