If the output width/height are not an even number of MCU's, then use an intermediate buffer to ensure that the output format is XVideo-compatible

git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@308 632fc199-4ca6-4c93-a231-07263d6284db

jpegut.c

@@ -226,13 +226,13 @@ int checkbuf(unsigned char *buf, int w, int h, int ps, int subsamp, int flags)
 #define PAD(v, p) ((v+(p)-1)&(~((p)-1)))
 
 int checkbufyuv(unsigned char *buf, unsigned long size, int w, int h,
-	int subsamp, int decode)
+	int subsamp)
 {
 	int i, j;
 	int hsf=_hsf[subsamp], vsf=_vsf[subsamp];
 	int pw=PAD(w, hsf), ph=PAD(h, vsf);
-	int cw=PAD(pw/hsf, decode? 8:1), ch=PAD(ph/vsf, decode? 8:1);
+	int cw=pw/hsf, ch=ph/vsf;
-	int ypitch=PAD(pw, decode? 8:4), uvpitch=PAD(cw, decode? 8:4);
+	int ypitch=PAD(pw, 4), uvpitch=PAD(cw, 4);
 	int retval=1;
 	unsigned long correctsize=ypitch*ph + (subsamp==TJ_GRAYSCALE? 0:uvpitch*ch*2);
 
@@ -389,7 +389,7 @@ void gentestjpeg(tjhandle hnd, unsigned char *jpegbuf, unsigned long *size,
 	writejpeg(jpegbuf, *size, tempstr);
 	if(yuv==YUVENCODE)
 	{
-		if(checkbufyuv(jpegbuf, *size, w, h, subsamp, 0)) printf("Passed.");
+		if(checkbufyuv(jpegbuf, *size, w, h, subsamp)) printf("Passed.");
 		else printf("FAILED!");
 	}
 	else printf("Done.");
@@ -406,7 +406,9 @@ void gentestbmp(tjhandle hnd, unsigned char *jpegbuf, unsigned long jpegsize,
 	const char *pixformat;  int _w=0, _h=0;  double t;
 	unsigned long size=0;
 	int hsf=_hsf[subsamp], vsf=_vsf[subsamp];
-	int pw=PAD(w, 8), ph=PAD(h, 8), cw=PAD(pw/hsf, 8), ch=PAD(ph/vsf, 8);
+	int pw=PAD(w, hsf), ph=PAD(h, vsf);
+	int cw=pw/hsf, ch=ph/vsf;
+	int ypitch=PAD(pw, 4), uvpitch=PAD(cw, 4);
 
 	if(yuv==YUVDECODE) flags|=TJ_YUV;
 	else if(yuv==YUVENCODE) return;
@@ -435,7 +437,7 @@ void gentestbmp(tjhandle hnd, unsigned char *jpegbuf, unsigned long jpegsize,
 	}
 
 	if(yuv==YUVDECODE)
-		size=pw*ph + (subsamp==TJ_GRAYSCALE? 0:cw*ch*(ps-1));
+		size=ypitch*ph + (subsamp==TJ_GRAYSCALE? 0:uvpitch*ch*2);
 	else
 		size=w*h*ps;
 	if((bmpbuf=(unsigned char *)malloc(size+1))==NULL)
@@ -450,7 +452,7 @@ void gentestbmp(tjhandle hnd, unsigned char *jpegbuf, unsigned long jpegsize,
 
 	if(yuv==YUVDECODE)
 	{
-		if(checkbufyuv(bmpbuf, size, pw, ph, subsamp, 1))
+		if(checkbufyuv(bmpbuf, size, pw, ph, subsamp))
 			printf("Passed.");
 		else printf("FAILED!");
 	}
@@ -589,7 +591,9 @@ int main(int argc, char *argv[])
 	if(doyuv)
 	{
 		yuv=YUVDECODE;
+		dotest(48, 48, 3, TJ_444, "test");
 		dotest(35, 39, 3, TJ_444, "test");
+		dotest(48, 48, 1, TJ_GRAYSCALE, "test");
 		dotest(39, 41, 1, TJ_GRAYSCALE, "test");
 	}
 

jpgtest.cxx

@@ -79,13 +79,15 @@ void dotest(unsigned char *srcbuf, int w, int h, BMPPIXELFORMAT pf, int bu,
 	int ps=_ps[pf];
 	int pitch=w*ps, yuvsize;
 	int hsf=_hsf[jpegsub], vsf=_vsf[jpegsub];
-	int pw=PAD(w, 8), ph=PAD(h, 8), cw=PAD(pw/hsf, 8), ch=PAD(ph/vsf, 8);
+	int pw=PAD(w, hsf), ph=PAD(h, vsf);
+	int cw=pw/hsf, ch=ph/vsf;
+	int ypitch=PAD(pw, 4), uvpitch=PAD(cw, 4);
 
 	flags |= _flags[pf];
 	if(bu) flags |= TJ_BOTTOMUP;
 	if(yuv==YUVENCODE) flags |= TJ_YUV;
 
-	yuvsize=pw*ph + (jpegsub==TJ_GRAYSCALE? 0:cw*ch*2);
+	yuvsize=ypitch*ph + (jpegsub==TJ_GRAYSCALE? 0:uvpitch*ch*2);
 	if((rgbbuf=(unsigned char *)malloc(max(yuvsize, pitch*h))) == NULL)
 		_throwunix("allocating image buffer");
 

turbojpeg.h

@@ -56,19 +56,23 @@ enum {TJ_444=0, TJ_422, TJ_420, TJ_GRAYSCALE};
 #define TJ_YUV           512
   /* If passed to tjCompress(), this causes TurboJPEG/OSS to use the
      accelerated color conversion routines in libjpeg-turbo to produce a planar
-     YUV image that is suitable for X Video.  Specifically, if a component is
+     YUV image that is suitable for X Video.  Specifically, if the chrominance
-     subsampled along the horizontal dimension, then the width of the plane for
+     components are subsampled along the horizontal dimension, then the width
-     that component is padded to 2 in the output image (same goes for the
+     of the luminance plane is padded to 2 in the output image (same goes for
-     height, if the component is subsampled along the vertical dimension.)
+     the height of the luminance plane, if the chrominance components are
-     Also, each line of each plane in the output image is padded to 4 bytes.
+     subsampled along the vertical dimension.)  Also, each line of each plane
-     Although this will work with any subsampling option, it is really only
+     in the output image is padded to 4 bytes.  Although this will work with
-     useful in combination with TJ_420, which produces an image compatible with
+     any subsampling option, it is really only useful in combination with
-     the I420 (AKA "YUV420P") format.
+     TJ_420, which produces an image compatible with the I420 (AKA "YUV420P")
+     format.
 
      If passed to tjDecompress(), this tells TurboJPEG/OSS to perform JPEG
      decompression but to leave out the color conversion step, so a planar YUV
-     image is generated instead of an RGB image.  In this case, the width and
+     image is generated instead of an RGB image.  The padding of the planes in
-     height of all planes are padded to 8 in the output image.
+     this image is the same as in the above case.  Note that, if the width or
+     height of the output image is not a multiple of 8 (or a multiple of 16
+     along any dimension in which chrominance subsampling is used), then an
+     intermediate buffer copy will be performed within TurboJPEG/OSS.
   */
 
 typedef void* tjhandle;

turbojpegl.c

@@ -406,11 +406,16 @@ DLLEXPORT int DLLCALL tjDecompress(tjhandle h,
 	int flags)
 {
 	int i, row;  JSAMPROW *row_pointer=NULL, *outbuf[MAX_COMPONENTS];
-	int cw[MAX_COMPONENTS], ch[MAX_COMPONENTS];
+	int cw[MAX_COMPONENTS], ch[MAX_COMPONENTS], iw[MAX_COMPONENTS],
+		tmpbufsize=0, usetmpbuf=0, th[MAX_COMPONENTS];
+	JSAMPLE *_tmpbuf=NULL;  JSAMPROW *tmpbuf[MAX_COMPONENTS];
 
 	checkhandle(h);
 
-	for(i=0; i<MAX_COMPONENTS; i++) outbuf[i]=NULL;
+	for(i=0; i<MAX_COMPONENTS; i++)
+	{
+		tmpbuf[i]=NULL;  outbuf[i]=NULL;
+	}
 
 	if(srcbuf==NULL || size<=0
 		|| dstbuf==NULL || width<=0 || pitch<0 || height<=0)
@@ -428,7 +433,11 @@ DLLEXPORT int DLLCALL tjDecompress(tjhandle h,
 	if(setjmp(j->jerr.jb))
 	{  // this will execute if LIBJPEG has an error
 		for(i=0; i<MAX_COMPONENTS; i++)
+		{
+			if(tmpbuf[i]!=NULL) free(tmpbuf[i]);
 			if(outbuf[i]!=NULL) free(outbuf[i]);
+		}
+		if(_tmpbuf) free(_tmpbuf);
 		if(row_pointer) free(row_pointer);
 		return -1;
 	}
@@ -446,14 +455,42 @@ DLLEXPORT int DLLCALL tjDecompress(tjhandle h,
 		for(i=0; i<dinfo->num_components; i++)
 		{
 			jpeg_component_info *compptr=&dinfo->comp_info[i];
-			cw[i]=compptr->width_in_blocks*DCTSIZE;
+			int ih;
-			ch[i]=compptr->height_in_blocks*DCTSIZE;
+			iw[i]=compptr->width_in_blocks*DCTSIZE;
+			ih=compptr->height_in_blocks*DCTSIZE;
+			cw[i]=PAD(width, dinfo->max_h_samp_factor)*compptr->h_samp_factor
+				/dinfo->max_h_samp_factor;
+			ch[i]=PAD(height, dinfo->max_v_samp_factor)*compptr->v_samp_factor
+				/dinfo->max_v_samp_factor;
+			if(iw[i]!=cw[i] || ih!=ch[i])
+			{
+				usetmpbuf=1;
+				th[i]=compptr->v_samp_factor*DCTSIZE/dinfo->max_v_samp_factor;
+				tmpbufsize+=iw[i]*th[i];
+			}
 			if((outbuf[i]=(JSAMPROW *)malloc(sizeof(JSAMPROW)*ch[i]))==NULL)
 				_throw("Memory allocation failed in tjInitDecompress()");
 			for(row=0; row<ch[i]; row++)
 			{
 				outbuf[i][row]=ptr;
-				ptr+=cw[i];
+				ptr+=PAD(cw[i], 4);
+			}
+		}
+		if(usetmpbuf)
+		{
+			if((_tmpbuf=(JSAMPLE *)malloc(sizeof(JSAMPLE)*tmpbufsize))==NULL)
+				_throw("Memory allocation failed in tjInitDecompress()");
+			ptr=_tmpbuf;
+			for(i=0; i<dinfo->num_components; i++)
+			{
+				jpeg_component_info *compptr=&dinfo->comp_info[i];
+				if((tmpbuf[i]=(JSAMPROW *)malloc(sizeof(JSAMPROW)*th[i]))==NULL)
+					_throw("Memory allocation failed in tjInitDecompress()");
+				for(row=0; row<th[i]; row++)
+				{
+					tmpbuf[i][row]=ptr;
+					ptr+=iw[i];
+				}
 			}
 		}
 	}
@@ -491,16 +528,32 @@ DLLEXPORT int DLLCALL tjDecompress(tjhandle h,
 	jpeg_start_decompress(&j->dinfo);
 	if(flags&TJ_YUV)
 	{
-		for(row=0; row<j->dinfo.output_height;
+		j_decompress_ptr dinfo=&j->dinfo;
-			row+=j->dinfo.max_v_samp_factor*DCTSIZE)
+		for(row=0; row<dinfo->output_height;
+			row+=dinfo->max_v_samp_factor*DCTSIZE)
 		{
 			JSAMPARRAY yuvptr[MAX_COMPONENTS];
-			for(i=0; i<j->dinfo.num_components; i++)
+			for(i=0; i<dinfo->num_components; i++)
 			{
-				jpeg_component_info *compptr=&j->dinfo.comp_info[i];
+				jpeg_component_info *compptr=&dinfo->comp_info[i];
-				yuvptr[i]=&outbuf[i][row*compptr->v_samp_factor/j->dinfo.max_v_samp_factor];
+				if(usetmpbuf) yuvptr[i]=tmpbuf[i];
+				else yuvptr[i]=&outbuf[i][row*compptr->v_samp_factor
+					/dinfo->max_v_samp_factor];
+			}
+			jpeg_read_raw_data(dinfo, yuvptr, dinfo->max_v_samp_factor*DCTSIZE);
+			if(usetmpbuf)
+			{
+				int j;
+				for(i=0; i<dinfo->num_components; i++)
+				{
+					jpeg_component_info *compptr=&dinfo->comp_info[i];
+					for(j=0; j<min(th[i], dinfo->output_height-row); j++)
+					{
+						memcpy(outbuf[i][row*compptr->v_samp_factor
+							/dinfo->max_v_samp_factor+j], tmpbuf[i][j], cw[i]);
+					}
+				}
 			}
-			jpeg_read_raw_data(&j->dinfo, yuvptr, j->dinfo.max_v_samp_factor*DCTSIZE);
 		}
 	}
 	else
@@ -514,7 +567,11 @@ DLLEXPORT int DLLCALL tjDecompress(tjhandle h,
 	jpeg_finish_decompress(&j->dinfo);
 
 	for(i=0; i<MAX_COMPONENTS; i++)
+	{
+		if(tmpbuf[i]) free(tmpbuf[i]);
 		if(outbuf[i]) free(outbuf[i]);
+	}
+	if(_tmpbuf) free(_tmpbuf);
 	if(row_pointer) free(row_pointer);
 	return 0;
 }