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TurboJPEG: Numerous documentation improvements

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- Wordsmithing, formatting, and grammar tweaks

- Various clarifications and corrections, including specifying whether
  a particular buffer or image is used as a source or destination

- Accommodate/mention features that were introduced since the API
  documentation was created.

- For clarity, use "packed-pixel" to describe uncompressed
  source/destination images that are not planar YUV.

- Use "row" rather than "line" to refer to a single horizontal group of
  pixels or component values, for consistency with the libjpeg API
  documentation.  (libjpeg also uses "scanline", which is a more archaic
  term.)

- Use "alignment" rather than "padding" to refer to the number of bytes
  by which a row's width is evenly divisible.  This consistifies the
  documention of the YUV functions and tjLoadImage().  ("Padding"
  typically refers to the number of bytes added to each row, which is
  not the same thing.)

- Remove all references to "the underlying codec."  Although the
  TurboJPEG API originated as a cross-platform wrapper for the Intel
  Integrated Performance Primitives, Sun mediaLib, QuickTime, and
  libjpeg, none of those TurboJPEG implementations has been maintained
  since 2009.  Nothing would prevent someone from implementing the
  TurboJPEG API without libjpeg-turbo, but such an implementation would
  not necessarily have an "underlying codec."  (It could be fully
  self-contained.)

- Use "destination image" rather than "output image", for consistency,
  or describe the type of image that will be output.

- Avoid the term "image buffer" and instead use "byte buffer" to
  refer to buffers that will hold JPEG images, or describe the type of
  image that will be contained in the buffer.  (The Java documentation
  doesn't use "byte buffer", because the buffer arrays literally have
  "byte" in front of them, and since Java doesn't have pointers, it is
  not possible for mere mortals to store any other type of data in those
  arrays.)

- C: Use "unified" to describe YUV images stored in a single buffer, for
  consistency with the Java documentation.

- Use "planar YUV" rather than "YUV planar".  Is is our convention to
  describe images using {component layout} {colorspace/pixel format}
  {image function}, e.g. "packed-pixel RGB source image" or "planar YUV
  destination image."

- C: Document the TurboJPEG API version in which a particular function
  or macro was introduced, and reorder the backward compatibility
  function stubs in turbojpeg.h alphabetically by API version.

- C: Use Markdown rather than HTML tags, where possible, in the Doxygen
  comments.
This commit is contained in:
DRC
2023-01-06 10:29:10 -06:00
parent b03ee8b835
commit 9a146f0f23
31 changed files with 1845 additions and 1716 deletions
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298
java/org/libjpegturbo/turbojpeg/TJDecompressor.java
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@@ -1,5 +1,6 @@
/*
* Copyright (C)2011-2015, 2018, 2022 D. R. Commander. All Rights Reserved.
* Copyright (C)2011-2015, 2018, 2022-2023 D. R. Commander.
* All Rights Reserved.
* Copyright (C)2015 Viktor Szathmáry. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -50,10 +51,12 @@ public class TJDecompressor implements Closeable {
/**
* Create a TurboJPEG decompressor instance and associate the JPEG source
* image stored in <code>jpegImage</code> with the newly created instance.
* image or "abbreviated table specification" (AKA "tables-only") datastream
* stored in <code>jpegImage</code> with the newly created instance.
*
* @param jpegImage JPEG image buffer (size of the JPEG image is assumed to
* be the length of the array.) This buffer is not modified.
* @param jpegImage buffer containing a JPEG source image or tables-only
* datastream. (The size of the JPEG image or datastream is assumed to be
* the length of the array.) This buffer is not modified.
*/
public TJDecompressor(byte[] jpegImage) throws TJException {
init();
@@ -62,12 +65,15 @@ public class TJDecompressor implements Closeable {
/**
* Create a TurboJPEG decompressor instance and associate the JPEG source
* image of length <code>imageSize</code> bytes stored in
* <code>jpegImage</code> with the newly created instance.
* image or "abbreviated table specification" (AKA "tables-only") datastream
* of length <code>imageSize</code> bytes stored in <code>jpegImage</code>
* with the newly created instance.
*
* @param jpegImage JPEG image buffer. This buffer is not modified.
* @param jpegImage buffer containing a JPEG source image or tables-only
* datastream. This buffer is not modified.
*
* @param imageSize size of the JPEG image (in bytes)
* @param imageSize size of the JPEG source image or tables-only datastream
* (in bytes)
*/
public TJDecompressor(byte[] jpegImage, int imageSize) throws TJException {
init();
@@ -75,11 +81,11 @@ public class TJDecompressor implements Closeable {
}
/**
* Create a TurboJPEG decompressor instance and associate the YUV planar
* Create a TurboJPEG decompressor instance and associate the planar YUV
* source image stored in <code>yuvImage</code> with the newly created
* instance.
*
* @param yuvImage {@link YUVImage} instance containing a YUV planar
* @param yuvImage {@link YUVImage} instance containing a planar YUV source
* image to be decoded. This image is not modified.
*/
@SuppressWarnings("checkstyle:HiddenField")
@@ -100,11 +106,11 @@ public class TJDecompressor implements Closeable {
* when decompressing video streams in which all frames share the same
* quantization and Huffman tables.
*
* @param jpegImage buffer containing a JPEG image or an "abbreviated table
* specification" (AKA "tables-only") datastream. This buffer is not
* modified.
* @param jpegImage buffer containing a JPEG source image or tables-only
* datastream. This buffer is not modified.
*
* @param imageSize size of the JPEG image (in bytes)
* @param imageSize size of the JPEG source image or tables-only datastream
* (in bytes)
*/
public void setSourceImage(byte[] jpegImage, int imageSize)
throws TJException {
@@ -127,12 +133,12 @@ public class TJDecompressor implements Closeable {
}
/**
* Associate the specified YUV planar source image with this decompressor
* instance. Subsequent decompress operations will decode this image into an
* RGB or grayscale destination image.
* Associate the specified planar YUV source image with this decompressor
* instance. Subsequent decompress operations will decode this image into a
* packed-pixel RGB or grayscale destination image.
*
* @param srcImage {@link YUVImage} instance containing a YUV planar image to
* be decoded. This image is not modified.
* @param srcImage {@link YUVImage} instance containing a planar YUV source
* image to be decoded. This image is not modified.
*/
public void setSourceImage(YUVImage srcImage) {
if (srcImage == null)
@@ -210,9 +216,9 @@ public class TJDecompressor implements Closeable {
}
/**
* Returns the JPEG image buffer associated with this decompressor instance.
* Returns the JPEG buffer associated with this decompressor instance.
*
* @return the JPEG image buffer associated with this decompressor instance.
* @return the JPEG buffer associated with this decompressor instance.
*/
public byte[] getJPEGBuf() {
if (jpegBuf == null)
@@ -239,14 +245,14 @@ public class TJDecompressor implements Closeable {
* height.
*
* @param desiredWidth desired width (in pixels) of the decompressed image.
* Setting this to 0 is the same as setting it to the width of the JPEG image
* (in other words, the width will not be considered when determining the
* scaled image size.)
* Setting this to 0 is the same as setting it to the width of the JPEG
* image. (In other words, the width will not be considered when determining
* the scaled image size.)
*
* @param desiredHeight desired height (in pixels) of the decompressed image.
* Setting this to 0 is the same as setting it to the height of the JPEG
* image (in other words, the height will not be considered when determining
* the scaled image size.)
* image. (In other words, the height will not be considered when
* determining the scaled image size.)
*
* @return the width of the largest scaled-down image that the TurboJPEG
* decompressor can generate without exceeding the desired image width and
@@ -280,14 +286,14 @@ public class TJDecompressor implements Closeable {
* height.
*
* @param desiredWidth desired width (in pixels) of the decompressed image.
* Setting this to 0 is the same as setting it to the width of the JPEG image
* (in other words, the width will not be considered when determining the
* scaled image size.)
* Setting this to 0 is the same as setting it to the width of the JPEG
* image. (In other words, the width will not be considered when determining
* the scaled image size.)
*
* @param desiredHeight desired height (in pixels) of the decompressed image.
* Setting this to 0 is the same as setting it to the height of the JPEG
* image (in other words, the height will not be considered when determining
* the scaled image size.)
* image. (In other words, the height will not be considered when
* determining the scaled image size.)
*
* @return the height of the largest scaled-down image that the TurboJPEG
* decompressor can generate without exceeding the desired image width and
@@ -316,27 +322,27 @@ public class TJDecompressor implements Closeable {
}
/**
* Decompress the JPEG source image or decode the YUV source image associated
* with this decompressor instance and output a grayscale, RGB, or CMYK image
* to the given destination buffer.
* Decompress the JPEG source image or decode the planar YUV source image
* associated with this decompressor instance and output a packed-pixel
* grayscale, RGB, or CMYK image to the given destination buffer.
* <p>
* NOTE: The output image is fully recoverable if this method throws a
* NOTE: The destination image is fully recoverable if this method throws a
* non-fatal {@link TJException} (unless
* {@link TJ#FLAG_STOPONWARNING TJ.FLAG_STOPONWARNING} is specified.)
*
* @param dstBuf buffer that will receive the decompressed/decoded image.
* If the source image is a JPEG image, then this buffer should normally be
* <code>pitch * scaledHeight</code> bytes in size, where
* <code>scaledHeight</code> can be determined by calling <code>
* scalingFactor.{@link TJScalingFactor#getScaled getScaled}(jpegHeight)
* </code> with one of the scaling factors returned from {@link
* TJ#getScalingFactors} or by calling {@link #getScaledHeight}. If the
* source image is a YUV image, then this buffer should normally be
* <code>pitch * height</code> bytes in size, where <code>height</code> is
* the height of the YUV image. However, the buffer may also be larger than
* the dimensions of the source image, in which case the <code>x</code>,
* <code>y</code>, and <code>pitch</code> parameters can be used to specify
* the region into which the source image should be decompressed/decoded.
* @param dstBuf buffer that will receive the packed-pixel
* decompressed/decoded image. If the source image is a JPEG image, then
* this buffer should normally be <code>pitch * scaledHeight</code> bytes in
* size, where <code>scaledHeight</code> can be determined by calling
* <code>scalingFactor.</code>{@link TJScalingFactor#getScaled getScaled}<code>(jpegHeight)</code>
* with one of the scaling factors returned from {@link TJ#getScalingFactors}
* or by calling {@link #getScaledHeight}. If the source image is a YUV
* image, then this buffer should normally be <code>pitch * height</code>
* bytes in size, where <code>height</code> is the height of the YUV image.
* However, the buffer may also be larger than the dimensions of the source
* image, in which case the <code>x</code>, <code>y</code>, and
* <code>pitch</code> parameters can be used to specify the region into which
* the source image should be decompressed/decoded.
*
* @param x x offset (in pixels) of the region in the destination image into
* which the source image should be decompressed/decoded
@@ -350,20 +356,20 @@ public class TJDecompressor implements Closeable {
* than the source image dimensions, then TurboJPEG will use scaling in the
* JPEG decompressor to generate the largest possible image that will fit
* within the desired dimensions. Setting this to 0 is the same as setting
* it to the width of the JPEG image (in other words, the width will not be
* it to the width of the JPEG image. (In other words, the width will not be
* considered when determining the scaled image size.) This parameter is
* ignored if the source image is a YUV image.
*
* @param pitch bytes per line of the destination image. Normally, this
* should be set to <code>scaledWidth * TJ.pixelSize(pixelFormat)</code> if
* the destination image is unpadded, but you can use this to, for instance,
* pad each line of the destination image to a 4-byte boundary or to
* decompress/decode the source image into a region of a larger image. NOTE:
* if the source image is a JPEG image, then <code>scaledWidth</code> can be
* determined by calling <code>
* scalingFactor.{@link TJScalingFactor#getScaled getScaled}(jpegWidth)
* </code> or by calling {@link #getScaledWidth}. If the source image is a
* YUV image, then <code>scaledWidth</code> is the width of the YUV image.
* @param pitch bytes per row in the destination image. Normally this should
* be set to <code>scaledWidth * TJ.pixelSize(pixelFormat)</code>, if the
* destination image will be unpadded. However, you can use this to, for
* instance, pad each row of the destination image to the nearest multiple of
* 4 bytes or to decompress/decode the source image into a region of a larger
* image. NOTE: if the source image is a JPEG image, then
* <code>scaledWidth</code> can be determined by calling
* <code>scalingFactor.</code>{@link TJScalingFactor#getScaled getScaled}<code>(jpegWidth)</code>
* or by calling {@link #getScaledWidth}. If the source image is a YUV
* image, then <code>scaledWidth</code> is the width of the YUV image.
* Setting this parameter to 0 is the equivalent of setting it to
* <code>scaledWidth * TJ.pixelSize(pixelFormat)</code>.
*
@@ -373,8 +379,8 @@ public class TJDecompressor implements Closeable {
* than the source image dimensions, then TurboJPEG will use scaling in the
* JPEG decompressor to generate the largest possible image that will fit
* within the desired dimensions. Setting this to 0 is the same as setting
* it to the height of the JPEG image (in other words, the height will not be
* considered when determining the scaled image size.) This parameter is
* it to the height of the JPEG image. (In other words, the height will not
* be considered when determining the scaled image size.) This parameter is
* ignored if the source image is a YUV image.
*
* @param pixelFormat pixel format of the decompressed/decoded image (one of
@@ -421,8 +427,9 @@ public class TJDecompressor implements Closeable {
}
/**
* Decompress the JPEG source image associated with this decompressor
* instance and return a buffer containing the decompressed image.
* Decompress the JPEG source image or decode the planar YUV source image
* associated with this decompressor instance and return a buffer containing
* the packed-pixel decompressed image.
*
* @param desiredWidth see
* {@link #decompress(byte[], int, int, int, int, int, int, int)}
@@ -442,7 +449,7 @@ public class TJDecompressor implements Closeable {
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*
* @return a buffer containing the decompressed image.
* @return a buffer containing the packed-pixel decompressed image.
*/
public byte[] decompress(int desiredWidth, int pitch, int desiredHeight,
int pixelFormat, int flags) throws TJException {
@@ -462,22 +469,22 @@ public class TJDecompressor implements Closeable {
/**
* Decompress the JPEG source image associated with this decompressor
* instance into a YUV planar image and store it in the given
* <code>YUVImage</code> instance. This method performs JPEG decompression
* but leaves out the color conversion step, so a planar YUV image is
* generated instead of an RGB or grayscale image. This method cannot be
* used to decompress JPEG source images with the CMYK or YCCK colorspace.
* instance into a planar YUV image and store it in the given
* {@link YUVImage} instance. This method performs JPEG decompression but
* leaves out the color conversion step, so a planar YUV image is generated
* instead of a packed-pixel image. This method cannot be used to decompress
* JPEG source images with the CMYK or YCCK colorspace.
* <p>
* NOTE: The YUV planar output image is fully recoverable if this method
* NOTE: The planar YUV destination image is fully recoverable if this method
* throws a non-fatal {@link TJException} (unless
* {@link TJ#FLAG_STOPONWARNING TJ.FLAG_STOPONWARNING} is specified.)
*
* @param dstImage {@link YUVImage} instance that will receive the YUV planar
* image. The level of subsampling specified in this <code>YUVImage</code>
* instance must match that of the JPEG image, and the width and height
* specified in the <code>YUVImage</code> instance must match one of the
* scaled image sizes that TurboJPEG is capable of generating from the JPEG
* source image.
* @param dstImage {@link YUVImage} instance that will receive the planar YUV
* decompressed image. The level of subsampling specified in this
* {@link YUVImage} instance must match that of the JPEG image, and the width
* and height specified in the {@link YUVImage} instance must match one of
* the scaled image sizes that the decompressor is capable of generating from
* the JPEG source image.
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
@@ -494,7 +501,7 @@ public class TJDecompressor implements Closeable {
dstImage.getHeight());
if (scaledWidth != dstImage.getWidth() ||
scaledHeight != dstImage.getHeight())
throw new IllegalArgumentException("YUVImage dimensions do not match one of the scaled image sizes that TurboJPEG is capable of generating.");
throw new IllegalArgumentException("YUVImage dimensions do not match one of the scaled image sizes that the decompressor is capable of generating.");
if (jpegSubsamp != dstImage.getSubsamp())
throw new IllegalArgumentException("YUVImage subsampling level does not match that of the JPEG image");
@@ -517,40 +524,41 @@ public class TJDecompressor implements Closeable {
/**
* Decompress the JPEG source image associated with this decompressor
* instance into a set of Y, U (Cb), and V (Cr) image planes and return a
* <code>YUVImage</code> instance containing the decompressed image planes.
* This method performs JPEG decompression but leaves out the color
* conversion step, so a planar YUV image is generated instead of an RGB or
* grayscale image. This method cannot be used to decompress JPEG source
* images with the CMYK or YCCK colorspace.
* {@link YUVImage} instance containing the decompressed image planes. This
* method performs JPEG decompression but leaves out the color conversion
* step, so a planar YUV image is generated instead of a packed-pixel image.
* This method cannot be used to decompress JPEG source images with the CMYK
* or YCCK colorspace.
*
* @param desiredWidth desired width (in pixels) of the YUV image. If the
* desired image dimensions are different than the dimensions of the JPEG
* image being decompressed, then TurboJPEG will use scaling in the JPEG
* decompressor to generate the largest possible image that will fit within
* the desired dimensions. Setting this to 0 is the same as setting it to
* the width of the JPEG image (in other words, the width will not be
* the width of the JPEG image. (In other words, the width will not be
* considered when determining the scaled image size.)
*
* @param strides an array of integers, each specifying the number of bytes
* per line in the corresponding plane of the output image. Setting the
* stride for any plane to 0 is the same as setting it to the scaled
* component width of the plane. If <tt>strides</tt> is NULL, then the
* strides for all planes will be set to their respective scaled component
* widths. You can adjust the strides in order to add an arbitrary amount of
* line padding to each plane.
* per row in the corresponding plane of the YUV image. Setting the stride
* for any plane to 0 is the same as setting it to the scaled plane width
* (see {@link YUVImage}.) If <code>strides</code> is null, then the strides
* for all planes will be set to their respective scaled plane widths. You
* can adjust the strides in order to add an arbitrary amount of row padding
* to each plane.
*
* @param desiredHeight desired height (in pixels) of the YUV image. If the
* desired image dimensions are different than the dimensions of the JPEG
* image being decompressed, then TurboJPEG will use scaling in the JPEG
* decompressor to generate the largest possible image that will fit within
* the desired dimensions. Setting this to 0 is the same as setting it to
* the height of the JPEG image (in other words, the height will not be
* the height of the JPEG image. (In other words, the height will not be
* considered when determining the scaled image size.)
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*
* @return a YUV planar image.
* @return a {@link YUVImage} instance containing the decompressed image
* planes
*/
public YUVImage decompressToYUV(int desiredWidth, int[] strides,
int desiredHeight,
@@ -574,40 +582,41 @@ public class TJDecompressor implements Closeable {
/**
* Decompress the JPEG source image associated with this decompressor
* instance into a unified YUV planar image buffer and return a
* <code>YUVImage</code> instance containing the decompressed image. This
* method performs JPEG decompression but leaves out the color conversion
* step, so a planar YUV image is generated instead of an RGB or grayscale
* image. This method cannot be used to decompress JPEG source images with
* the CMYK or YCCK colorspace.
* instance into a unified planar YUV image and return a {@link YUVImage}
* instance containing the decompressed image. This method performs JPEG
* decompression but leaves out the color conversion step, so a planar YUV
* image is generated instead of a packed-pixel image. This method cannot be
* used to decompress JPEG source images with the CMYK or YCCK colorspace.
*
* @param desiredWidth desired width (in pixels) of the YUV image. If the
* desired image dimensions are different than the dimensions of the JPEG
* image being decompressed, then TurboJPEG will use scaling in the JPEG
* decompressor to generate the largest possible image that will fit within
* the desired dimensions. Setting this to 0 is the same as setting it to
* the width of the JPEG image (in other words, the width will not be
* the width of the JPEG image. (In other words, the width will not be
* considered when determining the scaled image size.)
*
* @param pad the width of each line in each plane of the YUV image will be
* padded to the nearest multiple of this number of bytes (must be a power of
* 2.)
* @param align row alignment (in bytes) of the YUV image (must be a power of
* 2.) Setting this parameter to n will cause each row in each plane of the
* YUV image to be padded to the nearest multiple of n bytes (1 = unpadded.)
*
* @param desiredHeight desired height (in pixels) of the YUV image. If the
* desired image dimensions are different than the dimensions of the JPEG
* image being decompressed, then TurboJPEG will use scaling in the JPEG
* decompressor to generate the largest possible image that will fit within
* the desired dimensions. Setting this to 0 is the same as setting it to
* the height of the JPEG image (in other words, the height will not be
* the height of the JPEG image. (In other words, the height will not be
* considered when determining the scaled image size.)
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*
* @return a YUV planar image.
* @return a {@link YUVImage} instance containing the unified planar YUV
* decompressed image
*/
public YUVImage decompressToYUV(int desiredWidth, int pad, int desiredHeight,
int flags) throws TJException {
public YUVImage decompressToYUV(int desiredWidth, int align,
int desiredHeight, int flags)
throws TJException {
if (flags < 0)
throw new IllegalArgumentException("Invalid argument in decompressToYUV()");
if (jpegWidth < 1 || jpegHeight < 1 || jpegSubsamp < 0)
@@ -619,7 +628,7 @@ public class TJDecompressor implements Closeable {
int scaledWidth = getScaledWidth(desiredWidth, desiredHeight);
int scaledHeight = getScaledHeight(desiredWidth, desiredHeight);
YUVImage dstYUVImage = new YUVImage(scaledWidth, pad, scaledHeight,
YUVImage dstYUVImage = new YUVImage(scaledWidth, align, scaledHeight,
jpegSubsamp);
decompressToYUV(dstYUVImage, flags);
return dstYUVImage;
@@ -637,27 +646,27 @@ public class TJDecompressor implements Closeable {
}
/**
* Decompress the JPEG source image or decode the YUV source image associated
* with this decompressor instance and output a grayscale, RGB, or CMYK image
* to the given destination buffer.
* Decompress the JPEG source image or decode the planar YUV source image
* associated with this decompressor instance and output a packed-pixel
* grayscale, RGB, or CMYK image to the given destination buffer.
* <p>
* NOTE: The output image is fully recoverable if this method throws a
* NOTE: The destination image is fully recoverable if this method throws a
* non-fatal {@link TJException} (unless
* {@link TJ#FLAG_STOPONWARNING TJ.FLAG_STOPONWARNING} is specified.)
*
* @param dstBuf buffer that will receive the decompressed/decoded image.
* If the source image is a JPEG image, then this buffer should normally be
* <code>stride * scaledHeight</code> pixels in size, where
* <code>scaledHeight</code> can be determined by calling <code>
* scalingFactor.{@link TJScalingFactor#getScaled getScaled}(jpegHeight)
* </code> with one of the scaling factors returned from {@link
* TJ#getScalingFactors} or by calling {@link #getScaledHeight}. If the
* source image is a YUV image, then this buffer should normally be
* <code>stride * height</code> pixels in size, where <code>height</code> is
* the height of the YUV image. However, the buffer may also be larger than
* the dimensions of the JPEG image, in which case the <code>x</code>,
* <code>y</code>, and <code>stride</code> parameters can be used to specify
* the region into which the source image should be decompressed.
* @param dstBuf buffer that will receive the packed-pixel
* decompressed/decoded image. If the source image is a JPEG image, then
* this buffer should normally be <code>stride * scaledHeight</code> pixels
* in size, where <code>scaledHeight</code> can be determined by calling
* <code>scalingFactor.</code>{@link TJScalingFactor#getScaled getScaled}<code>(jpegHeight)</code>
* with one of the scaling factors returned from {@link TJ#getScalingFactors}
* or by calling {@link #getScaledHeight}. If the source image is a YUV
* image, then this buffer should normally be <code>stride * height</code>
* pixels in size, where <code>height</code> is the height of the YUV image.
* However, the buffer may also be larger than the dimensions of the JPEG
* image, in which case the <code>x</code>, <code>y</code>, and
* <code>stride</code> parameters can be used to specify the region into
* which the source image should be decompressed.
*
* @param x x offset (in pixels) of the region in the destination image into
* which the source image should be decompressed/decoded
@@ -671,18 +680,18 @@ public class TJDecompressor implements Closeable {
* than the source image dimensions, then TurboJPEG will use scaling in the
* JPEG decompressor to generate the largest possible image that will fit
* within the desired dimensions. Setting this to 0 is the same as setting
* it to the width of the JPEG image (in other words, the width will not be
* it to the width of the JPEG image. (In other words, the width will not be
* considered when determining the scaled image size.) This parameter is
* ignored if the source image is a YUV image.
*
* @param stride pixels per line of the destination image. Normally, this
* @param stride pixels per row in the destination image. Normally this
* should be set to <code>scaledWidth</code>, but you can use this to, for
* instance, decompress the JPEG image into a region of a larger image.
* NOTE: if the source image is a JPEG image, then <code>scaledWidth</code>
* can be determined by calling <code>
* scalingFactor.{@link TJScalingFactor#getScaled getScaled}(jpegWidth)
* </code> or by calling {@link #getScaledWidth}. If the source image is a
* YUV image, then <code>scaledWidth</code> is the width of the YUV image.
* can be determined by calling
* <code>scalingFactor.</code>{@link TJScalingFactor#getScaled getScaled}<code>(jpegWidth)</code>
* or by calling {@link #getScaledWidth}. If the source image is a YUV
* image, then <code>scaledWidth</code> is the width of the YUV image.
* Setting this parameter to 0 is the equivalent of setting it to
* <code>scaledWidth</code>.
*
@@ -692,8 +701,8 @@ public class TJDecompressor implements Closeable {
* than the source image dimensions, then TurboJPEG will use scaling in the
* JPEG decompressor to generate the largest possible image that will fit
* within the desired dimensions. Setting this to 0 is the same as setting
* it to the height of the JPEG image (in other words, the height will not be
* considered when determining the scaled image size.) This parameter is
* it to the height of the JPEG image. (In other words, the height will not
* be considered when determining the scaled image size.) This parameter is
* ignored if the source image is a YUV image.
*
* @param pixelFormat pixel format of the decompressed image (one of
@@ -722,21 +731,22 @@ public class TJDecompressor implements Closeable {
}
/**
* Decompress the JPEG source image or decode the YUV source image associated
* with this decompressor instance and output a decompressed/decoded image to
* the given <code>BufferedImage</code> instance.
* Decompress the JPEG source image or decode the planar YUV source image
* associated with this decompressor instance and output a packed-pixel
* decompressed/decoded image to the given <code>BufferedImage</code>
* instance.
* <p>
* NOTE: The output image is fully recoverable if this method throws a
* NOTE: The destination image is fully recoverable if this method throws a
* non-fatal {@link TJException} (unless
* {@link TJ#FLAG_STOPONWARNING TJ.FLAG_STOPONWARNING} is specified.)
*
* @param dstImage a <code>BufferedImage</code> instance that will receive
* the decompressed/decoded image. If the source image is a JPEG image, then
* the width and height of the <code>BufferedImage</code> instance must match
* one of the scaled image sizes that TurboJPEG is capable of generating from
* the JPEG image. If the source image is a YUV image, then the width and
* height of the <code>BufferedImage</code> instance must match the width and
* height of the YUV image.
* the packed-pixel decompressed/decoded image. If the source image is a
* JPEG image, then the width and height of the <code>BufferedImage</code>
* instance must match one of the scaled image sizes that the decompressor is
* capable of generating from the JPEG image. If the source image is a YUV
* image, then the width and height of the <code>BufferedImage</code>
* instance must match the width and height of the YUV image.
*
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
@@ -759,7 +769,7 @@ public class TJDecompressor implements Closeable {
scaledWidth = getScaledWidth(desiredWidth, desiredHeight);
scaledHeight = getScaledHeight(desiredWidth, desiredHeight);
if (scaledWidth != desiredWidth || scaledHeight != desiredHeight)
throw new IllegalArgumentException("BufferedImage dimensions do not match one of the scaled image sizes that TurboJPEG is capable of generating.");
throw new IllegalArgumentException("BufferedImage dimensions do not match one of the scaled image sizes that the decompressor is capable of generating.");
}
int pixelFormat; boolean intPixels = false;
if (byteOrder == null)
@@ -829,7 +839,7 @@ public class TJDecompressor implements Closeable {
/**
* Decompress the JPEG source image or decode the YUV source image associated
* with this decompressor instance and return a <code>BufferedImage</code>
* instance containing the decompressed/decoded image.
* instance containing the packed-pixel decompressed/decoded image.
*
* @param desiredWidth see
* {@link #decompress(byte[], int, int, int, int, int, int, int)} for
@@ -846,7 +856,7 @@ public class TJDecompressor implements Closeable {
* @param flags the bitwise OR of one or more of
* {@link TJ#FLAG_BOTTOMUP TJ.FLAG_*}
*
* @return a <code>BufferedImage</code> instance containing the
* @return a <code>BufferedImage</code> instance containing the packed-pixel
* decompressed/decoded image.
*/
public BufferedImage decompress(int desiredWidth, int desiredHeight,