/modules/libpr0n/encoders/png/nsPNGEncoder.cpp
C++ | 590 lines | 374 code | 98 blank | 118 comment | 167 complexity | 33bf5b0c87bdc7714960cd39dabcf666 MD5 | raw file
Possible License(s): LGPL-3.0, MIT, BSD-3-Clause, MPL-2.0-no-copyleft-exception, GPL-2.0, LGPL-2.1
- /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
- * ***** BEGIN LICENSE BLOCK *****
- * Version: MPL 1.1/GPL 2.0/LGPL 2.1
- *
- * The contents of this file are subject to the Mozilla Public License Version
- * 1.1 (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- * for the specific language governing rights and limitations under the
- * License.
- *
- * The Original Code is PNG Encoding code
- *
- * The Initial Developer of the Original Code is
- * Google Inc.
- * Portions created by the Initial Developer are Copyright (C) 2005
- * the Initial Developer. All Rights Reserved.
- *
- * Contributor(s):
- * Brett Wilson <brettw@gmail.com>
- * Stuart Parmenter <pavlov@pavlov.net>
- * Justin Dolske <dolske@mozilla.com>
- *
- * Alternatively, the contents of this file may be used under the terms of
- * either the GNU General Public License Version 2 or later (the "GPL"), or
- * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- * in which case the provisions of the GPL or the LGPL are applicable instead
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
- #include "nsCRT.h"
- #include "nsPNGEncoder.h"
- #include "prmem.h"
- #include "prprf.h"
- #include "nsString.h"
- #include "nsStreamUtils.h"
- // Input streams that do not implement nsIAsyncInputStream should be threadsafe
- // so that they may be used with nsIInputStreamPump and nsIInputStreamChannel,
- // which read such a stream on a background thread.
- NS_IMPL_THREADSAFE_ISUPPORTS2(nsPNGEncoder, imgIEncoder, nsIInputStream)
- nsPNGEncoder::nsPNGEncoder() : mPNG(nsnull), mPNGinfo(nsnull),
- mIsAnimation(PR_FALSE),
- mImageBuffer(nsnull), mImageBufferSize(0),
- mImageBufferUsed(0), mImageBufferReadPoint(0)
- {
- }
- nsPNGEncoder::~nsPNGEncoder()
- {
- if (mImageBuffer) {
- PR_Free(mImageBuffer);
- mImageBuffer = nsnull;
- }
- // don't leak if EndImageEncode wasn't called
- if (mPNG)
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- }
- // nsPNGEncoder::InitFromData
- //
- // One output option is supported: "transparency=none" means that the
- // output PNG will not have an alpha channel, even if the input does.
- //
- // Based partially on gfx/cairo/cairo/src/cairo-png.c
- // See also modules/libimg/png/libpng.txt
- NS_IMETHODIMP nsPNGEncoder::InitFromData(const PRUint8* aData,
- PRUint32 aLength, // (unused, req'd by JS)
- PRUint32 aWidth,
- PRUint32 aHeight,
- PRUint32 aStride,
- PRUint32 aInputFormat,
- const nsAString& aOutputOptions)
- {
- nsresult rv;
- rv = StartImageEncode(aWidth, aHeight, aInputFormat, aOutputOptions);
- if (!NS_SUCCEEDED(rv))
- return rv;
- rv = AddImageFrame(aData, aLength, aWidth, aHeight, aStride, aInputFormat, aOutputOptions);
- if (!NS_SUCCEEDED(rv))
- return rv;
- rv = EndImageEncode();
- return rv;
- }
- // nsPNGEncoder::StartImageEncode
- //
- //
- // See ::InitFromData for other info.
- NS_IMETHODIMP nsPNGEncoder::StartImageEncode(PRUint32 aWidth,
- PRUint32 aHeight,
- PRUint32 aInputFormat,
- const nsAString& aOutputOptions)
- {
- PRBool useTransparency = PR_TRUE, skipFirstFrame = PR_FALSE;
- PRUint32 numFrames = 1;
- PRUint32 numPlays = 0; // For animations, 0 == forever
- // can't initialize more than once
- if (mImageBuffer != nsnull)
- return NS_ERROR_ALREADY_INITIALIZED;
- // validate input format
- if (aInputFormat != INPUT_FORMAT_RGB &&
- aInputFormat != INPUT_FORMAT_RGBA &&
- aInputFormat != INPUT_FORMAT_HOSTARGB)
- return NS_ERROR_INVALID_ARG;
- // parse and check any provided output options
- nsresult rv = ParseOptions(aOutputOptions, &useTransparency, &skipFirstFrame,
- &numFrames, &numPlays, nsnull, nsnull,
- nsnull, nsnull, nsnull);
- if (rv != NS_OK) { return rv; }
- if (numFrames > 1) {
- mIsAnimation = PR_TRUE;
- }
- // initialize
- mPNG = png_create_write_struct(PNG_LIBPNG_VER_STRING,
- nsnull,
- ErrorCallback,
- ErrorCallback);
- if (! mPNG)
- return NS_ERROR_OUT_OF_MEMORY;
- mPNGinfo = png_create_info_struct(mPNG);
- if (! mPNGinfo) {
- png_destroy_write_struct(&mPNG, nsnull);
- return NS_ERROR_FAILURE;
- }
- // libpng's error handler jumps back here upon an error.
- // Note: It's important that all png_* callers do this, or errors
- // will result in a corrupt time-warped stack.
- if (setjmp(png_jmpbuf(mPNG))) {
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- return NS_ERROR_FAILURE;
- }
- // Set up to read the data into our image buffer, start out with an 8K
- // estimated size. Note: we don't have to worry about freeing this data
- // in this function. It will be freed on object destruction.
- mImageBufferSize = 8192;
- mImageBuffer = (PRUint8*)PR_Malloc(mImageBufferSize);
- if (!mImageBuffer) {
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- return NS_ERROR_OUT_OF_MEMORY;
- }
- mImageBufferUsed = 0;
- // set our callback for libpng to give us the data
- png_set_write_fn(mPNG, this, WriteCallback, NULL);
- // include alpha?
- int colorType;
- if ((aInputFormat == INPUT_FORMAT_HOSTARGB ||
- aInputFormat == INPUT_FORMAT_RGBA) && useTransparency)
- colorType = PNG_COLOR_TYPE_RGB_ALPHA;
- else
- colorType = PNG_COLOR_TYPE_RGB;
- png_set_IHDR(mPNG, mPNGinfo, aWidth, aHeight, 8, colorType,
- PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
- PNG_FILTER_TYPE_DEFAULT);
- if (mIsAnimation) {
- png_set_first_frame_is_hidden(mPNG, mPNGinfo, skipFirstFrame);
- png_set_acTL(mPNG, mPNGinfo, numFrames, numPlays);
- }
- // XXX: support PLTE, gAMA, tRNS, bKGD?
- png_write_info(mPNG, mPNGinfo);
- return NS_OK;
- }
- NS_IMETHODIMP nsPNGEncoder::AddImageFrame(const PRUint8* aData,
- PRUint32 aLength, // (unused, req'd by JS)
- PRUint32 aWidth,
- PRUint32 aHeight,
- PRUint32 aStride,
- PRUint32 aInputFormat,
- const nsAString& aFrameOptions)
- {
- PRBool useTransparency= PR_TRUE;
- PRUint32 delay_ms = 500;
- PRUint32 dispose_op = PNG_DISPOSE_OP_NONE;
- PRUint32 blend_op = PNG_BLEND_OP_SOURCE;
- PRUint32 x_offset = 0, y_offset = 0;
- // must be initialized
- if (mImageBuffer == nsnull)
- return NS_ERROR_NOT_INITIALIZED;
- // EndImageEncode was done, or some error occurred earlier
- if (!mPNG)
- return NS_BASE_STREAM_CLOSED;
- // validate input format
- if (aInputFormat != INPUT_FORMAT_RGB &&
- aInputFormat != INPUT_FORMAT_RGBA &&
- aInputFormat != INPUT_FORMAT_HOSTARGB)
- return NS_ERROR_INVALID_ARG;
- // libpng's error handler jumps back here upon an error.
- if (setjmp(png_jmpbuf(mPNG))) {
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- return NS_ERROR_FAILURE;
- }
- // parse and check any provided output options
- nsresult rv = ParseOptions(aFrameOptions, &useTransparency, nsnull,
- nsnull, nsnull, &dispose_op, &blend_op,
- &delay_ms, &x_offset, &y_offset);
- if (rv != NS_OK) { return rv; }
- if (mIsAnimation) {
- // XXX the row pointers arg (#3) is unused, can it be removed?
- png_write_frame_head(mPNG, mPNGinfo, nsnull,
- aWidth, aHeight, x_offset, y_offset,
- delay_ms, 1000, dispose_op, blend_op);
- }
- // Stride is the padded width of each row, so it better be longer (I'm afraid
- // people will not understand what stride means, so check it well)
- if ((aInputFormat == INPUT_FORMAT_RGB &&
- aStride < aWidth * 3) ||
- ((aInputFormat == INPUT_FORMAT_RGBA || aInputFormat == INPUT_FORMAT_HOSTARGB) &&
- aStride < aWidth * 4)) {
- NS_WARNING("Invalid stride for InitFromData/AddImageFrame");
- return NS_ERROR_INVALID_ARG;
- }
- // write each row: if we add more input formats, we may want to
- // generalize the conversions
- if (aInputFormat == INPUT_FORMAT_HOSTARGB) {
- // PNG requires RGBA with post-multiplied alpha, so we need to convert
- PRUint8* row = new PRUint8[aWidth * 4];
- for (PRUint32 y = 0; y < aHeight; y ++) {
- ConvertHostARGBRow(&aData[y * aStride], row, aWidth, useTransparency);
- png_write_row(mPNG, row);
- }
- delete[] row;
- } else if (aInputFormat == INPUT_FORMAT_RGBA && ! useTransparency) {
- // RBGA, but we need to strip the alpha
- PRUint8* row = new PRUint8[aWidth * 4];
- for (PRUint32 y = 0; y < aHeight; y ++) {
- StripAlpha(&aData[y * aStride], row, aWidth);
- png_write_row(mPNG, row);
- }
- delete[] row;
- } else if (aInputFormat == INPUT_FORMAT_RGB ||
- aInputFormat == INPUT_FORMAT_RGBA) {
- // simple RBG(A), no conversion needed
- for (PRUint32 y = 0; y < aHeight; y ++) {
- png_write_row(mPNG, (PRUint8*)&aData[y * aStride]);
- }
- } else {
- NS_NOTREACHED("Bad format type");
- return NS_ERROR_INVALID_ARG;
- }
- if (mIsAnimation) {
- png_write_frame_tail(mPNG, mPNGinfo);
- }
- return NS_OK;
- }
- NS_IMETHODIMP nsPNGEncoder::EndImageEncode()
- {
- // must be initialized
- if (mImageBuffer == nsnull)
- return NS_ERROR_NOT_INITIALIZED;
- // EndImageEncode has already been called, or some error occurred earlier
- if (!mPNG)
- return NS_BASE_STREAM_CLOSED;
- // libpng's error handler jumps back here upon an error.
- if (setjmp(png_jmpbuf(mPNG))) {
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- return NS_ERROR_FAILURE;
- }
- png_write_end(mPNG, mPNGinfo);
- png_destroy_write_struct(&mPNG, &mPNGinfo);
- // if output callback can't get enough memory, it will free our buffer
- if (!mImageBuffer)
- return NS_ERROR_OUT_OF_MEMORY;
- return NS_OK;
- }
- nsresult
- nsPNGEncoder::ParseOptions(const nsAString& aOptions,
- PRBool* useTransparency,
- PRBool* skipFirstFrame,
- PRUint32* numFrames,
- PRUint32* numPlays,
- PRUint32* frameDispose,
- PRUint32* frameBlend,
- PRUint32* frameDelay,
- PRUint32* offsetX,
- PRUint32* offsetY)
- {
- // Make a copy of aOptions, because strtok() will modify it.
- nsCAutoString optionsCopy;
- optionsCopy.Assign(NS_ConvertUTF16toUTF8(aOptions));
- char* options = optionsCopy.BeginWriting();
- while (char* token = nsCRT::strtok(options, ";", &options)) {
- // If there's an '=' character, split the token around it.
- char* equals = token, *value = nsnull;
- while(*equals != '=' && *equals) { ++equals; }
- if (*equals == '=') { value = equals + 1; }
- if (value) { *equals = '\0'; } // temporary null
- // transparency=[yes|no|none]
- if (nsCRT::strcmp(token, "transparency") == 0 && useTransparency) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (nsCRT::strcmp(value, "none") == 0 || nsCRT::strcmp(value, "no") == 0) {
- *useTransparency = PR_FALSE;
- } else if (nsCRT::strcmp(value, "yes") == 0) {
- *useTransparency = PR_TRUE;
- } else {
- return NS_ERROR_INVALID_ARG;
- }
- // skipfirstframe=[yes|no]
- } else if (nsCRT::strcmp(token, "skipfirstframe") == 0 && skipFirstFrame) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (nsCRT::strcmp(value, "no") == 0) {
- *skipFirstFrame = PR_FALSE;
- } else if (nsCRT::strcmp(value, "yes") == 0) {
- *skipFirstFrame = PR_TRUE;
- } else {
- return NS_ERROR_INVALID_ARG;
- }
- // frames=#
- } else if (nsCRT::strcmp(token, "frames") == 0 && numFrames) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (PR_sscanf(value, "%u", numFrames) != 1) { return NS_ERROR_INVALID_ARG; }
- // frames=0 is nonsense.
- if (*numFrames == 0) { return NS_ERROR_INVALID_ARG; }
- // plays=#
- } else if (nsCRT::strcmp(token, "plays") == 0 && numPlays) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- // plays=0 to loop forever, otherwise play sequence specified number of times
- if (PR_sscanf(value, "%u", numPlays) != 1) { return NS_ERROR_INVALID_ARG; }
- // dispose=[none|background|previous]
- } else if (nsCRT::strcmp(token, "dispose") == 0 && frameDispose) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (nsCRT::strcmp(value, "none") == 0) {
- *frameDispose = PNG_DISPOSE_OP_NONE;
- } else if (nsCRT::strcmp(value, "background") == 0) {
- *frameDispose = PNG_DISPOSE_OP_BACKGROUND;
- } else if (nsCRT::strcmp(value, "previous") == 0) {
- *frameDispose = PNG_DISPOSE_OP_PREVIOUS;
- } else {
- return NS_ERROR_INVALID_ARG;
- }
- // blend=[source|over]
- } else if (nsCRT::strcmp(token, "blend") == 0 && frameBlend) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (nsCRT::strcmp(value, "source") == 0) {
- *frameBlend = PNG_BLEND_OP_SOURCE;
- } else if (nsCRT::strcmp(value, "over") == 0) {
- *frameBlend = PNG_BLEND_OP_OVER;
- } else {
- return NS_ERROR_INVALID_ARG;
- }
- // delay=# (in ms)
- } else if (nsCRT::strcmp(token, "delay") == 0 && frameDelay) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (PR_sscanf(value, "%u", frameDelay) != 1) { return NS_ERROR_INVALID_ARG; }
- // xoffset=#
- } else if (nsCRT::strcmp(token, "xoffset") == 0 && offsetX) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (PR_sscanf(value, "%u", offsetX) != 1) { return NS_ERROR_INVALID_ARG; }
- // yoffset=#
- } else if (nsCRT::strcmp(token, "yoffset") == 0 && offsetY) {
- if (!value) { return NS_ERROR_INVALID_ARG; }
- if (PR_sscanf(value, "%u", offsetY) != 1) { return NS_ERROR_INVALID_ARG; }
- // unknown token name
- } else {
- return NS_ERROR_INVALID_ARG;
- }
- if (value) { *equals = '='; } // restore '=' so strtok doesn't get lost
- }
- return NS_OK;
- }
- /* void close (); */
- NS_IMETHODIMP nsPNGEncoder::Close()
- {
- if (mImageBuffer != nsnull) {
- PR_Free(mImageBuffer);
- mImageBuffer = nsnull;
- mImageBufferSize = 0;
- mImageBufferUsed = 0;
- mImageBufferReadPoint = 0;
- }
- return NS_OK;
- }
- /* unsigned long available (); */
- NS_IMETHODIMP nsPNGEncoder::Available(PRUint32 *_retval)
- {
- if (!mImageBuffer)
- return NS_BASE_STREAM_CLOSED;
- *_retval = mImageBufferUsed - mImageBufferReadPoint;
- return NS_OK;
- }
- /* [noscript] unsigned long read (in charPtr aBuf, in unsigned long aCount); */
- NS_IMETHODIMP nsPNGEncoder::Read(char * aBuf, PRUint32 aCount,
- PRUint32 *_retval)
- {
- return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, _retval);
- }
- /* [noscript] unsigned long readSegments (in nsWriteSegmentFun aWriter, in voidPtr aClosure, in unsigned long aCount); */
- NS_IMETHODIMP nsPNGEncoder::ReadSegments(nsWriteSegmentFun aWriter,
- void *aClosure, PRUint32 aCount,
- PRUint32 *_retval)
- {
- PRUint32 maxCount = mImageBufferUsed - mImageBufferReadPoint;
- if (maxCount == 0) {
- *_retval = 0;
- return NS_OK;
- }
- if (aCount > maxCount)
- aCount = maxCount;
- nsresult rv = aWriter(this, aClosure,
- reinterpret_cast<const char*>(mImageBuffer+mImageBufferReadPoint),
- 0, aCount, _retval);
- if (NS_SUCCEEDED(rv)) {
- NS_ASSERTION(*_retval <= aCount, "bad write count");
- mImageBufferReadPoint += *_retval;
- }
- // errors returned from the writer end here!
- return NS_OK;
- }
- /* boolean isNonBlocking (); */
- NS_IMETHODIMP nsPNGEncoder::IsNonBlocking(PRBool *_retval)
- {
- *_retval = PR_FALSE; // We don't implement nsIAsyncInputStream
- return NS_OK;
- }
- // nsPNGEncoder::ConvertHostARGBRow
- //
- // Our colors are stored with premultiplied alphas, but PNGs use
- // post-multiplied alpha. This swaps to PNG-style alpha.
- //
- // Copied from gfx/cairo/cairo/src/cairo-png.c
- void
- nsPNGEncoder::ConvertHostARGBRow(const PRUint8* aSrc, PRUint8* aDest,
- PRUint32 aPixelWidth, PRBool aUseTransparency)
- {
- PRUint32 pixelStride = aUseTransparency ? 4 : 3;
- for (PRUint32 x = 0; x < aPixelWidth; x ++) {
- const PRUint32& pixelIn = ((const PRUint32*)(aSrc))[x];
- PRUint8 *pixelOut = &aDest[x * pixelStride];
- PRUint8 alpha = (pixelIn & 0xff000000) >> 24;
- if (alpha == 0) {
- pixelOut[0] = pixelOut[1] = pixelOut[2] = pixelOut[3] = 0;
- } else {
- pixelOut[0] = (((pixelIn & 0xff0000) >> 16) * 255 + alpha / 2) / alpha;
- pixelOut[1] = (((pixelIn & 0x00ff00) >> 8) * 255 + alpha / 2) / alpha;
- pixelOut[2] = (((pixelIn & 0x0000ff) >> 0) * 255 + alpha / 2) / alpha;
- if (aUseTransparency)
- pixelOut[3] = alpha;
- }
- }
- }
- // nsPNGEncoder::StripAlpha
- //
- // Input is RGBA, output is RGB
- void
- nsPNGEncoder::StripAlpha(const PRUint8* aSrc, PRUint8* aDest,
- PRUint32 aPixelWidth)
- {
- for (PRUint32 x = 0; x < aPixelWidth; x ++) {
- const PRUint8* pixelIn = &aSrc[x * 4];
- PRUint8* pixelOut = &aDest[x * 3];
- pixelOut[0] = pixelIn[0];
- pixelOut[1] = pixelIn[1];
- pixelOut[2] = pixelIn[2];
- }
- }
- // nsPNGEncoder::ErrorCallback
- void // static
- nsPNGEncoder::ErrorCallback(png_structp png_ptr, png_const_charp warning_msg)
- {
- #ifdef DEBUG
- // XXX: these messages are probably useful callers... use nsIConsoleService?
- PR_fprintf(PR_STDERR, "PNG Encoder: %s\n", warning_msg);;
- #endif
- }
- // nsPNGEncoder::WriteCallback
- void // static
- nsPNGEncoder::WriteCallback(png_structp png, png_bytep data, png_size_t size)
- {
- nsPNGEncoder* that = static_cast<nsPNGEncoder*>(png_get_io_ptr(png));
- if (! that->mImageBuffer)
- return;
- if (that->mImageBufferUsed + size > that->mImageBufferSize) {
- // expand buffer, just double each time
- that->mImageBufferSize *= 2;
- PRUint8* newBuf = (PRUint8*)PR_Realloc(that->mImageBuffer,
- that->mImageBufferSize);
- if (! newBuf) {
- // can't resize, just zero (this will keep us from writing more)
- PR_Free(that->mImageBuffer);
- that->mImageBufferSize = 0;
- that->mImageBufferUsed = 0;
- return;
- }
- that->mImageBuffer = newBuf;
- }
- memcpy(&that->mImageBuffer[that->mImageBufferUsed], data, size);
- that->mImageBufferUsed += size;
- }