void nsGIFDecoder2::FlushImageData() { switch (mCurrentPass - mLastFlushedPass) { case 0: // same pass if (mCurrentRow - mLastFlushedRow) FlushImageData(mLastFlushedRow + 1, mCurrentRow - mLastFlushedRow); break; case 1: // one pass on - need to handle bottom & top rects FlushImageData(0, mCurrentRow + 1); FlushImageData(mLastFlushedRow + 1, mGIFStruct.height - (mLastFlushedRow + 1)); break; default: // more than one pass on - push the whole frame FlushImageData(0, mGIFStruct.height); } }
//****************************************************************************** void nsGIFDecoder2::EndImageFrame() { // First flush all pending image data if (!mGIFStruct.images_decoded) { // Only need to flush first frame FlushImageData(); // If the first frame is smaller in height than the entire image, send an // invalidation for the area it does not have data for. // This will clear the remaining bits of the placeholder. (Bug 37589) const PRUint32 realFrameHeight = mGIFStruct.height + mGIFStruct.y_offset; if (realFrameHeight < mGIFStruct.screen_height) { nsIntRect r(0, realFrameHeight, mGIFStruct.screen_width, mGIFStruct.screen_height - realFrameHeight); PostInvalidation(r); } // This transparency check is only valid for first frame if (mGIFStruct.is_transparent && !mSawTransparency) { mImage->SetFrameHasNoAlpha(mGIFStruct.images_decoded); } } mCurrentRow = mLastFlushedRow = -1; mCurrentPass = mLastFlushedPass = 0; // Only add frame if we have any rows at all if (mGIFStruct.rows_remaining != mGIFStruct.height) { if (mGIFStruct.rows_remaining && mGIFStruct.images_decoded) { // Clear the remaining rows (only needed for the animation frames) PRUint8 *rowp = mImageData + ((mGIFStruct.height - mGIFStruct.rows_remaining) * mGIFStruct.width); memset(rowp, 0, mGIFStruct.rows_remaining * mGIFStruct.width); } // We actually have the timeout information before we get the lzw encoded // image data, at least according to the spec, but we delay in setting the // timeout for the image until here to help ensure that we have the whole // image frame decoded before we go off and try to display another frame. mImage->SetFrameTimeout(mGIFStruct.images_decoded, mGIFStruct.delay_time); } // Unconditionally increment images_decoded, because we unconditionally // append frames in BeginImageFrame(). This ensures that images_decoded // always refers to the frame in mImage we're currently decoding, // even if some of them weren't decoded properly and thus are blank. mGIFStruct.images_decoded++; // Tell the superclass we finished a frame PostFrameStop(); // Reset the transparent pixel if (mOldColor) { mColormap[mGIFStruct.tpixel] = mOldColor; mOldColor = 0; } mCurrentFrame = -1; }
//****************************************************************************** void nsGIFDecoder2::EndImageFrame() { FrameBlender::FrameAlpha alpha = FrameBlender::kFrameHasAlpha; // First flush all pending image data if (!mGIFStruct.images_decoded) { // Only need to flush first frame FlushImageData(); // If the first frame is smaller in height than the entire image, send an // invalidation for the area it does not have data for. // This will clear the remaining bits of the placeholder. (Bug 37589) const uint32_t realFrameHeight = mGIFStruct.height + mGIFStruct.y_offset; if (realFrameHeight < mGIFStruct.screen_height) { nsIntRect r(0, realFrameHeight, mGIFStruct.screen_width, mGIFStruct.screen_height - realFrameHeight); PostInvalidation(r); } // This transparency check is only valid for first frame if (mGIFStruct.is_transparent && !mSawTransparency) { alpha = FrameBlender::kFrameOpaque; } } mCurrentRow = mLastFlushedRow = -1; mCurrentPass = mLastFlushedPass = 0; // Only add frame if we have any rows at all if (mGIFStruct.rows_remaining != mGIFStruct.height) { if (mGIFStruct.rows_remaining && mGIFStruct.images_decoded) { // Clear the remaining rows (only needed for the animation frames) uint8_t *rowp = mImageData + ((mGIFStruct.height - mGIFStruct.rows_remaining) * mGIFStruct.width); memset(rowp, 0, mGIFStruct.rows_remaining * mGIFStruct.width); } } // Unconditionally increment images_decoded, because we unconditionally // append frames in BeginImageFrame(). This ensures that images_decoded // always refers to the frame in mImage we're currently decoding, // even if some of them weren't decoded properly and thus are blank. mGIFStruct.images_decoded++; // Tell the superclass we finished a frame PostFrameStop(alpha, FrameBlender::FrameDisposalMethod(mGIFStruct.disposal_method), mGIFStruct.delay_time); // Reset the transparent pixel if (mOldColor) { mColormap[mGIFStruct.tpixel] = mOldColor; mOldColor = 0; } mCurrentFrameIndex = -1; }
nsresult nsGIFDecoder2::FlushImageData() { nsresult rv = NS_OK; switch (mCurrentPass - mLastFlushedPass) { case 0: // same pass if (mCurrentRow - mLastFlushedRow) rv = FlushImageData(mLastFlushedRow + 1, mCurrentRow - mLastFlushedRow); break; case 1: // one pass on - need to handle bottom & top rects rv = FlushImageData(0, mCurrentRow + 1); rv |= FlushImageData(mLastFlushedRow + 1, mGIFStruct.height - (mLastFlushedRow + 1)); break; default: // more than one pass on - push the whole frame rv = FlushImageData(0, mGIFStruct.height); } return rv; }
/* void write (in string aBuffer, in PRUint32 aCount); */ NS_IMETHODIMP nsGIFDecoder2::Write(const char *aBuffer, PRUint32 aCount) { // Don't forgive previously flagged errors if (mError) return NS_ERROR_FAILURE; // Push the data to the GIF decoder nsresult rv = GifWrite((const unsigned char *)aBuffer, aCount); // Flushing is only needed for first frame if (NS_SUCCEEDED(rv) && !mGIFStruct.images_decoded) { rv = FlushImageData(); NS_ENSURE_SUCCESS(rv, rv); mLastFlushedRow = mCurrentRow; mLastFlushedPass = mCurrentPass; } // We do some fine-grained error control here. If we have at least one frame // of an animated gif, we still want to display it (mostly for legacy reasons). // libpr0n code is strict, so we have to lie and tell it we were successful. So // if we have something to salvage, we send off final decode notifications, and // pretend that we're decoded. Otherwise, we set mError. if (NS_FAILED(rv)) { // Determine if we want to salvage the situation PRUint32 numFrames = 0; if (mImageContainer) mImageContainer->GetNumFrames(&numFrames); // If we're salvaging, send off notifications // Note that we need to make sure that we have 2 frames, since that tells us // that the first frame is complete (the second could be in any state). if (numFrames > 1) { EndGIF(/* aSuccess = */ PR_TRUE); } // Otherwise, set mError else mError = PR_TRUE; } return mError ? NS_ERROR_FAILURE : NS_OK; }
void nsGIFDecoder2::WriteInternal(const char *aBuffer, uint32_t aCount, DecodeStrategy) { NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!"); // These variables changed names, and renaming would make a much bigger patch :( const uint8_t *buf = (const uint8_t *)aBuffer; uint32_t len = aCount; const uint8_t *q = buf; // Add what we have sofar to the block // If previous call to me left something in the hold first complete current block // Or if we are filling the colormaps, first complete the colormap uint8_t* p = (mGIFStruct.state == gif_global_colormap) ? (uint8_t*)mGIFStruct.global_colormap : (mGIFStruct.state == gif_image_colormap) ? (uint8_t*)mColormap : (mGIFStruct.bytes_in_hold) ? mGIFStruct.hold : nullptr; if (len == 0 && buf == nullptr) { // We've just gotten the frame we asked for. Time to use the data we // stashed away. len = mGIFStruct.bytes_in_hold; q = buf = p; } else if (p) { // Add what we have sofar to the block uint32_t l = std::min(len, mGIFStruct.bytes_to_consume); memcpy(p+mGIFStruct.bytes_in_hold, buf, l); if (l < mGIFStruct.bytes_to_consume) { // Not enough in 'buf' to complete current block, get more mGIFStruct.bytes_in_hold += l; mGIFStruct.bytes_to_consume -= l; return; } // Point 'q' to complete block in hold (or in colormap) q = p; } // Invariant: // 'q' is start of current to be processed block (hold, colormap or buf) // 'bytes_to_consume' is number of bytes to consume from 'buf' // 'buf' points to the bytes to be consumed from the input buffer // 'len' is number of bytes left in input buffer from position 'buf'. // At entrance of the for loop will 'buf' will be moved 'bytes_to_consume' // to point to next buffer, 'len' is adjusted accordingly. // So that next round in for loop, q gets pointed to the next buffer. for (;len >= mGIFStruct.bytes_to_consume; q=buf, mGIFStruct.bytes_in_hold = 0) { // Eat the current block from the buffer, q keeps pointed at current block buf += mGIFStruct.bytes_to_consume; len -= mGIFStruct.bytes_to_consume; switch (mGIFStruct.state) { case gif_lzw: if (!DoLzw(q)) { mGIFStruct.state = gif_error; break; } GETN(1, gif_sub_block); break; case gif_lzw_start: { // Make sure the transparent pixel is transparent in the colormap if (mGIFStruct.is_transparent) { // Save old value so we can restore it later if (mColormap == mGIFStruct.global_colormap) mOldColor = mColormap[mGIFStruct.tpixel]; mColormap[mGIFStruct.tpixel] = 0; } /* Initialize LZW parser/decoder */ mGIFStruct.datasize = *q; const int clear_code = ClearCode(); if (mGIFStruct.datasize > MAX_LZW_BITS || clear_code >= MAX_BITS) { mGIFStruct.state = gif_error; break; } mGIFStruct.avail = clear_code + 2; mGIFStruct.oldcode = -1; mGIFStruct.codesize = mGIFStruct.datasize + 1; mGIFStruct.codemask = (1 << mGIFStruct.codesize) - 1; mGIFStruct.datum = mGIFStruct.bits = 0; /* init the tables */ for (int i = 0; i < clear_code; i++) mGIFStruct.suffix[i] = i; mGIFStruct.stackp = mGIFStruct.stack; GETN(1, gif_sub_block); } break; /* All GIF files begin with "GIF87a" or "GIF89a" */ case gif_type: if (!strncmp((char*)q, "GIF89a", 6)) { mGIFStruct.version = 89; } else if (!strncmp((char*)q, "GIF87a", 6)) { mGIFStruct.version = 87; } else { mGIFStruct.state = gif_error; break; } GETN(7, gif_global_header); break; case gif_global_header: /* This is the height and width of the "screen" or * frame into which images are rendered. The * individual images can be smaller than the * screen size and located with an origin anywhere * within the screen. */ mGIFStruct.screen_width = GETINT16(q); mGIFStruct.screen_height = GETINT16(q + 2); mGIFStruct.global_colormap_depth = (q[4]&0x07) + 1; if (IsSizeDecode()) { MOZ_ASSERT(!mGIFOpen, "Gif should not be open at this point"); PostSize(mGIFStruct.screen_width, mGIFStruct.screen_height); return; } // screen_bgcolor is not used //mGIFStruct.screen_bgcolor = q[5]; // q[6] = Pixel Aspect Ratio // Not used // float aspect = (float)((q[6] + 15) / 64.0); if (q[4] & 0x80) { /* global map */ // Get the global colormap const uint32_t size = (3 << mGIFStruct.global_colormap_depth); if (len < size) { // Use 'hold' pattern to get the global colormap GETN(size, gif_global_colormap); break; } // Copy everything, go to colormap state to do CMS correction memcpy(mGIFStruct.global_colormap, buf, size); buf += size; len -= size; GETN(0, gif_global_colormap); break; } GETN(1, gif_image_start); break; case gif_global_colormap: // Everything is already copied into global_colormap // Convert into Cairo colors including CMS transformation ConvertColormap(mGIFStruct.global_colormap, 1<<mGIFStruct.global_colormap_depth); GETN(1, gif_image_start); break; case gif_image_start: switch (*q) { case GIF_TRAILER: mGIFStruct.state = gif_done; break; case GIF_EXTENSION_INTRODUCER: GETN(2, gif_extension); break; case GIF_IMAGE_SEPARATOR: GETN(9, gif_image_header); break; default: /* If we get anything other than GIF_IMAGE_SEPARATOR, * GIF_EXTENSION_INTRODUCER, or GIF_TRAILER, there is extraneous data * between blocks. The GIF87a spec tells us to keep reading * until we find an image separator, but GIF89a says such * a file is corrupt. We follow GIF89a and bail out. */ if (mGIFStruct.images_decoded > 0) { /* The file is corrupt, but one or more images have * been decoded correctly. In this case, we proceed * as if the file were correctly terminated and set * the state to gif_done, so the GIF will display. */ mGIFStruct.state = gif_done; } else { /* No images decoded, there is nothing to display. */ mGIFStruct.state = gif_error; } } break; case gif_extension: mGIFStruct.bytes_to_consume = q[1]; if (mGIFStruct.bytes_to_consume) { switch (*q) { case GIF_GRAPHIC_CONTROL_LABEL: // The GIF spec mandates that the GIFControlExtension header block length is 4 bytes, // and the parser for this block reads 4 bytes, so we must enforce that the buffer // contains at least this many bytes. If the GIF specifies a different length, we // allow that, so long as it's larger; the additional data will simply be ignored. mGIFStruct.state = gif_control_extension; mGIFStruct.bytes_to_consume = std::max(mGIFStruct.bytes_to_consume, 4u); break; // The GIF spec also specifies the lengths of the following two extensions' headers // (as 12 and 11 bytes, respectively). Because we ignore the plain text extension entirely // and sanity-check the actual length of the application extension header before reading it, // we allow GIFs to deviate from these values in either direction. This is important for // real-world compatibility, as GIFs in the wild exist with application extension headers // that are both shorter and longer than 11 bytes. case GIF_APPLICATION_EXTENSION_LABEL: mGIFStruct.state = gif_application_extension; break; case GIF_PLAIN_TEXT_LABEL: mGIFStruct.state = gif_skip_block; break; case GIF_COMMENT_LABEL: mGIFStruct.state = gif_consume_comment; break; default: mGIFStruct.state = gif_skip_block; } } else { GETN(1, gif_image_start); } break; case gif_consume_block: if (!*q) GETN(1, gif_image_start); else GETN(*q, gif_skip_block); break; case gif_skip_block: GETN(1, gif_consume_block); break; case gif_control_extension: mGIFStruct.is_transparent = *q & 0x1; mGIFStruct.tpixel = q[3]; mGIFStruct.disposal_method = ((*q) >> 2) & 0x7; // Some specs say 3rd bit (value 4), other specs say value 3 // Let's choose 3 (the more popular) if (mGIFStruct.disposal_method == 4) mGIFStruct.disposal_method = 3; mGIFStruct.delay_time = GETINT16(q + 1) * 10; GETN(1, gif_consume_block); break; case gif_comment_extension: if (*q) GETN(*q, gif_consume_comment); else GETN(1, gif_image_start); break; case gif_consume_comment: GETN(1, gif_comment_extension); break; case gif_application_extension: /* Check for netscape application extension */ if (mGIFStruct.bytes_to_consume == 11 && (!strncmp((char*)q, "NETSCAPE2.0", 11) || !strncmp((char*)q, "ANIMEXTS1.0", 11))) GETN(1, gif_netscape_extension_block); else GETN(1, gif_consume_block); break; /* Netscape-specific GIF extension: animation looping */ case gif_netscape_extension_block: if (*q) // We might need to consume 3 bytes in // gif_consume_netscape_extension, so make sure we have at least that. GETN(std::max(3, static_cast<int>(*q)), gif_consume_netscape_extension); else GETN(1, gif_image_start); break; /* Parse netscape-specific application extensions */ case gif_consume_netscape_extension: switch (q[0] & 7) { case 1: /* Loop entire animation specified # of times. Only read the loop count during the first iteration. */ mGIFStruct.loop_count = GETINT16(q + 1); GETN(1, gif_netscape_extension_block); break; case 2: /* Wait for specified # of bytes to enter buffer */ // Don't do this, this extension doesn't exist (isn't used at all) // and doesn't do anything, as our streaming/buffering takes care of it all... // See: http://semmix.pl/color/exgraf/eeg24.htm GETN(1, gif_netscape_extension_block); break; default: // 0,3-7 are yet to be defined netscape extension codes mGIFStruct.state = gif_error; } break; case gif_image_header: { /* Get image offsets, with respect to the screen origin */ mGIFStruct.x_offset = GETINT16(q); mGIFStruct.y_offset = GETINT16(q + 2); /* Get image width and height. */ mGIFStruct.width = GETINT16(q + 4); mGIFStruct.height = GETINT16(q + 6); if (!mGIFStruct.images_decoded) { /* Work around broken GIF files where the logical screen * size has weird width or height. We assume that GIF87a * files don't contain animations. */ if ((mGIFStruct.screen_height < mGIFStruct.height) || (mGIFStruct.screen_width < mGIFStruct.width) || (mGIFStruct.version == 87)) { mGIFStruct.screen_height = mGIFStruct.height; mGIFStruct.screen_width = mGIFStruct.width; mGIFStruct.x_offset = 0; mGIFStruct.y_offset = 0; } // Create the image container with the right size. BeginGIF(); if (HasError()) { // Setting the size led to an error. mGIFStruct.state = gif_error; return; } // If we were doing a size decode, we're done if (IsSizeDecode()) return; } /* Work around more broken GIF files that have zero image width or height */ if (!mGIFStruct.height || !mGIFStruct.width) { mGIFStruct.height = mGIFStruct.screen_height; mGIFStruct.width = mGIFStruct.screen_width; if (!mGIFStruct.height || !mGIFStruct.width) { mGIFStruct.state = gif_error; break; } } /* Depth of colors is determined by colormap */ /* (q[8] & 0x80) indicates local colormap */ /* bits per pixel is (q[8]&0x07 + 1) when local colormap is set */ uint32_t depth = mGIFStruct.global_colormap_depth; if (q[8] & 0x80) depth = (q[8]&0x07) + 1; uint32_t realDepth = depth; while (mGIFStruct.tpixel >= (1 << realDepth) && (realDepth < 8)) { realDepth++; } // Mask to limit the color values within the colormap mColorMask = 0xFF >> (8 - realDepth); BeginImageFrame(realDepth); if (NeedsNewFrame()) { // We now need a new frame from the decoder framework. We leave all our // data in the buffer as if it wasn't consumed, copy to our hold and return // to the decoder framework. uint32_t size = len + mGIFStruct.bytes_to_consume + mGIFStruct.bytes_in_hold; if (size) { if (SetHold(q, mGIFStruct.bytes_to_consume + mGIFStruct.bytes_in_hold, buf, len)) { // Back into the decoder infrastructure so we can get called again. GETN(9, gif_image_header_continue); return; } } break; } else { // FALL THROUGH } } case gif_image_header_continue: { // While decoders can reuse frames, we unconditionally increment // mGIFStruct.images_decoded when we're done with a frame, so we both can // and need to zero out the colormap and image data after every new frame. memset(mImageData, 0, mImageDataLength); if (mColormap) { memset(mColormap, 0, mColormapSize); } if (!mGIFStruct.images_decoded) { // Send a onetime invalidation for the first frame if it has a y-axis offset. // Otherwise, the area may never be refreshed and the placeholder will remain // on the screen. (Bug 37589) if (mGIFStruct.y_offset > 0) { nsIntRect r(0, 0, mGIFStruct.screen_width, mGIFStruct.y_offset); PostInvalidation(r); } } if (q[8] & 0x40) { mGIFStruct.interlaced = true; mGIFStruct.ipass = 1; } else { mGIFStruct.interlaced = false; mGIFStruct.ipass = 0; } /* Only apply the Haeberli display hack on the first frame */ mGIFStruct.progressive_display = (mGIFStruct.images_decoded == 0); /* Clear state from last image */ mGIFStruct.irow = 0; mGIFStruct.rows_remaining = mGIFStruct.height; mGIFStruct.rowp = mImageData; /* Depth of colors is determined by colormap */ /* (q[8] & 0x80) indicates local colormap */ /* bits per pixel is (q[8]&0x07 + 1) when local colormap is set */ uint32_t depth = mGIFStruct.global_colormap_depth; if (q[8] & 0x80) depth = (q[8]&0x07) + 1; uint32_t realDepth = depth; while (mGIFStruct.tpixel >= (1 << realDepth) && (realDepth < 8)) { realDepth++; } if (q[8] & 0x80) /* has a local colormap? */ { mGIFStruct.local_colormap_size = 1 << depth; if (!mGIFStruct.images_decoded) { // First frame has local colormap, allocate space for it // as the image frame doesn't have its own palette mColormapSize = sizeof(uint32_t) << realDepth; if (!mGIFStruct.local_colormap) { mGIFStruct.local_colormap = (uint32_t*)moz_xmalloc(mColormapSize); } mColormap = mGIFStruct.local_colormap; } const uint32_t size = 3 << depth; if (mColormapSize > size) { // Clear the notfilled part of the colormap memset(((uint8_t*)mColormap) + size, 0, mColormapSize - size); } if (len < size) { // Use 'hold' pattern to get the image colormap GETN(size, gif_image_colormap); break; } // Copy everything, go to colormap state to do CMS correction memcpy(mColormap, buf, size); buf += size; len -= size; GETN(0, gif_image_colormap); break; } else { /* Switch back to the global palette */ if (mGIFStruct.images_decoded) { // Copy global colormap into the palette of current frame memcpy(mColormap, mGIFStruct.global_colormap, mColormapSize); } else { mColormap = mGIFStruct.global_colormap; } } GETN(1, gif_lzw_start); } break; case gif_image_colormap: // Everything is already copied into local_colormap // Convert into Cairo colors including CMS transformation ConvertColormap(mColormap, mGIFStruct.local_colormap_size); GETN(1, gif_lzw_start); break; case gif_sub_block: mGIFStruct.count = *q; if (mGIFStruct.count) { /* Still working on the same image: Process next LZW data block */ /* Make sure there are still rows left. If the GIF data */ /* is corrupt, we may not get an explicit terminator. */ if (!mGIFStruct.rows_remaining) { #ifdef DONT_TOLERATE_BROKEN_GIFS mGIFStruct.state = gif_error; break; #else /* This is an illegal GIF, but we remain tolerant. */ GETN(1, gif_sub_block); #endif if (mGIFStruct.count == GIF_TRAILER) { /* Found a terminator anyway, so consider the image done */ GETN(1, gif_done); break; } } GETN(mGIFStruct.count, gif_lzw); } else { /* See if there are any more images in this sequence. */ EndImageFrame(); GETN(1, gif_image_start); } break; case gif_done: MOZ_ASSERT(!IsSizeDecode(), "Size decodes shouldn't reach gif_done"); FinishInternal(); goto done; case gif_error: PostDataError(); return; // We shouldn't ever get here. default: break; } } // if an error state is set but no data remains, code flow reaches here if (mGIFStruct.state == gif_error) { PostDataError(); return; } // Copy the leftover into mGIFStruct.hold if (len) { // Add what we have sofar to the block if (mGIFStruct.state != gif_global_colormap && mGIFStruct.state != gif_image_colormap) { if (!SetHold(buf, len)) { PostDataError(); return; } } else { uint8_t* p = (mGIFStruct.state == gif_global_colormap) ? (uint8_t*)mGIFStruct.global_colormap : (uint8_t*)mColormap; memcpy(p, buf, len); mGIFStruct.bytes_in_hold = len; } mGIFStruct.bytes_to_consume -= len; } // We want to flush before returning if we're on the first frame done: if (!mGIFStruct.images_decoded) { FlushImageData(); mLastFlushedRow = mCurrentRow; mLastFlushedPass = mCurrentPass; } return; }
//****************************************************************************** void nsGIFDecoder2::EndImageFrame() { Opacity opacity = Opacity::SOME_TRANSPARENCY; // First flush all pending image data if (!mGIFStruct.images_decoded) { // Only need to flush first frame FlushImageData(); // If the first frame is smaller in height than the entire image, send an // invalidation for the area it does not have data for. // This will clear the remaining bits of the placeholder. (Bug 37589) const uint32_t realFrameHeight = mGIFStruct.height + mGIFStruct.y_offset; if (realFrameHeight < mGIFStruct.screen_height) { nsIntRect r(0, realFrameHeight, mGIFStruct.screen_width, mGIFStruct.screen_height - realFrameHeight); PostInvalidation(r); } // The first frame was preallocated with alpha; if it wasn't transparent, we // should fix that. We can also mark it opaque unconditionally if we didn't // actually see any transparent pixels - this test is only valid for the // first frame. if (!mGIFStruct.is_transparent || !mSawTransparency) { opacity = Opacity::OPAQUE; } } mCurrentRow = mLastFlushedRow = -1; mCurrentPass = mLastFlushedPass = 0; // Only add frame if we have any rows at all if (mGIFStruct.rows_remaining != mGIFStruct.height) { if (mGIFStruct.rows_remaining && mGIFStruct.images_decoded) { // Clear the remaining rows (only needed for the animation frames) uint8_t* rowp = mImageData + ((mGIFStruct.height - mGIFStruct.rows_remaining) * mGIFStruct.width); memset(rowp, 0, mGIFStruct.rows_remaining * mGIFStruct.width); } } // Unconditionally increment images_decoded, because we unconditionally // append frames in BeginImageFrame(). This ensures that images_decoded // always refers to the frame in mImage we're currently decoding, // even if some of them weren't decoded properly and thus are blank. mGIFStruct.images_decoded++; // Tell the superclass we finished a frame PostFrameStop(opacity, DisposalMethod(mGIFStruct.disposal_method), mGIFStruct.delay_time); // Reset the transparent pixel if (mOldColor) { mColormap[mGIFStruct.tpixel] = mOldColor; mOldColor = 0; } mCurrentFrameIndex = -1; }