diff options
Diffstat (limited to 'drivers/webp/demux/anim_decode.c')
| -rw-r--r-- | drivers/webp/demux/anim_decode.c | 442 |
1 files changed, 0 insertions, 442 deletions
diff --git a/drivers/webp/demux/anim_decode.c b/drivers/webp/demux/anim_decode.c deleted file mode 100644 index 39cf3de197..0000000000 --- a/drivers/webp/demux/anim_decode.c +++ /dev/null @@ -1,442 +0,0 @@ -// Copyright 2015 Google Inc. All Rights Reserved. -// -// Use of this source code is governed by a BSD-style license -// that can be found in the COPYING file in the root of the source -// tree. An additional intellectual property rights grant can be found -// in the file PATENTS. All contributing project authors may -// be found in the AUTHORS file in the root of the source tree. -// ----------------------------------------------------------------------------- -// -// AnimDecoder implementation. -// - -#ifdef HAVE_CONFIG_H -#include "webp/config.h" -#endif - -#include <assert.h> -#include <string.h> - -#include "../utils/utils.h" -#include "webp/decode.h" -#include "webp/demux.h" - -#define NUM_CHANNELS 4 - -typedef void (*BlendRowFunc)(uint32_t* const, const uint32_t* const, int); -static void BlendPixelRowNonPremult(uint32_t* const src, - const uint32_t* const dst, int num_pixels); -static void BlendPixelRowPremult(uint32_t* const src, const uint32_t* const dst, - int num_pixels); - -struct WebPAnimDecoder { - WebPDemuxer* demux_; // Demuxer created from given WebP bitstream. - WebPDecoderConfig config_; // Decoder config. - // Note: we use a pointer to a function blending multiple pixels at a time to - // allow possible inlining of per-pixel blending function. - BlendRowFunc blend_func_; // Pointer to the chose blend row function. - WebPAnimInfo info_; // Global info about the animation. - uint8_t* curr_frame_; // Current canvas (not disposed). - uint8_t* prev_frame_disposed_; // Previous canvas (properly disposed). - int prev_frame_timestamp_; // Previous frame timestamp (milliseconds). - WebPIterator prev_iter_; // Iterator object for previous frame. - int prev_frame_was_keyframe_; // True if previous frame was a keyframe. - int next_frame_; // Index of the next frame to be decoded - // (starting from 1). -}; - -static void DefaultDecoderOptions(WebPAnimDecoderOptions* const dec_options) { - dec_options->color_mode = MODE_RGBA; - dec_options->use_threads = 0; -} - -int WebPAnimDecoderOptionsInitInternal(WebPAnimDecoderOptions* dec_options, - int abi_version) { - if (dec_options == NULL || - WEBP_ABI_IS_INCOMPATIBLE(abi_version, WEBP_DEMUX_ABI_VERSION)) { - return 0; - } - DefaultDecoderOptions(dec_options); - return 1; -} - -static int ApplyDecoderOptions(const WebPAnimDecoderOptions* const dec_options, - WebPAnimDecoder* const dec) { - WEBP_CSP_MODE mode; - WebPDecoderConfig* config = &dec->config_; - assert(dec_options != NULL); - - mode = dec_options->color_mode; - if (mode != MODE_RGBA && mode != MODE_BGRA && - mode != MODE_rgbA && mode != MODE_bgrA) { - return 0; - } - dec->blend_func_ = (mode == MODE_RGBA || mode == MODE_BGRA) - ? &BlendPixelRowNonPremult - : &BlendPixelRowPremult; - WebPInitDecoderConfig(config); - config->output.colorspace = mode; - config->output.is_external_memory = 1; - config->options.use_threads = dec_options->use_threads; - // Note: config->output.u.RGBA is set at the time of decoding each frame. - return 1; -} - -WebPAnimDecoder* WebPAnimDecoderNewInternal( - const WebPData* webp_data, const WebPAnimDecoderOptions* dec_options, - int abi_version) { - WebPAnimDecoderOptions options; - WebPAnimDecoder* dec = NULL; - if (webp_data == NULL || - WEBP_ABI_IS_INCOMPATIBLE(abi_version, WEBP_DEMUX_ABI_VERSION)) { - return NULL; - } - - // Note: calloc() so that the pointer members are initialized to NULL. - dec = (WebPAnimDecoder*)WebPSafeCalloc(1ULL, sizeof(*dec)); - if (dec == NULL) goto Error; - - if (dec_options != NULL) { - options = *dec_options; - } else { - DefaultDecoderOptions(&options); - } - if (!ApplyDecoderOptions(&options, dec)) goto Error; - - dec->demux_ = WebPDemux(webp_data); - if (dec->demux_ == NULL) goto Error; - - dec->info_.canvas_width = WebPDemuxGetI(dec->demux_, WEBP_FF_CANVAS_WIDTH); - dec->info_.canvas_height = WebPDemuxGetI(dec->demux_, WEBP_FF_CANVAS_HEIGHT); - dec->info_.loop_count = WebPDemuxGetI(dec->demux_, WEBP_FF_LOOP_COUNT); - dec->info_.bgcolor = WebPDemuxGetI(dec->demux_, WEBP_FF_BACKGROUND_COLOR); - dec->info_.frame_count = WebPDemuxGetI(dec->demux_, WEBP_FF_FRAME_COUNT); - - { - const int canvas_bytes = - dec->info_.canvas_width * NUM_CHANNELS * dec->info_.canvas_height; - // Note: calloc() because we fill frame with zeroes as well. - dec->curr_frame_ = WebPSafeCalloc(1ULL, canvas_bytes); - if (dec->curr_frame_ == NULL) goto Error; - dec->prev_frame_disposed_ = WebPSafeCalloc(1ULL, canvas_bytes); - if (dec->prev_frame_disposed_ == NULL) goto Error; - } - - WebPAnimDecoderReset(dec); - - return dec; - - Error: - WebPAnimDecoderDelete(dec); - return NULL; -} - -int WebPAnimDecoderGetInfo(const WebPAnimDecoder* dec, WebPAnimInfo* info) { - if (dec == NULL || info == NULL) return 0; - *info = dec->info_; - return 1; -} - -// Returns true if the frame covers the full canvas. -static int IsFullFrame(int width, int height, int canvas_width, - int canvas_height) { - return (width == canvas_width && height == canvas_height); -} - -// Clear the canvas to transparent. -static void ZeroFillCanvas(uint8_t* buf, uint32_t canvas_width, - uint32_t canvas_height) { - memset(buf, 0, canvas_width * NUM_CHANNELS * canvas_height); -} - -// Clear given frame rectangle to transparent. -static void ZeroFillFrameRect(uint8_t* buf, int buf_stride, int x_offset, - int y_offset, int width, int height) { - int j; - assert(width * NUM_CHANNELS <= buf_stride); - buf += y_offset * buf_stride + x_offset * NUM_CHANNELS; - for (j = 0; j < height; ++j) { - memset(buf, 0, width * NUM_CHANNELS); - buf += buf_stride; - } -} - -// Copy width * height pixels from 'src' to 'dst'. -static void CopyCanvas(const uint8_t* src, uint8_t* dst, - uint32_t width, uint32_t height) { - assert(src != NULL && dst != NULL); - memcpy(dst, src, width * NUM_CHANNELS * height); -} - -// Returns true if the current frame is a key-frame. -static int IsKeyFrame(const WebPIterator* const curr, - const WebPIterator* const prev, - int prev_frame_was_key_frame, - int canvas_width, int canvas_height) { - if (curr->frame_num == 1) { - return 1; - } else if ((!curr->has_alpha || curr->blend_method == WEBP_MUX_NO_BLEND) && - IsFullFrame(curr->width, curr->height, - canvas_width, canvas_height)) { - return 1; - } else { - return (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) && - (IsFullFrame(prev->width, prev->height, canvas_width, - canvas_height) || - prev_frame_was_key_frame); - } -} - - -// Blend a single channel of 'src' over 'dst', given their alpha channel values. -// 'src' and 'dst' are assumed to be NOT pre-multiplied by alpha. -static uint8_t BlendChannelNonPremult(uint32_t src, uint8_t src_a, - uint32_t dst, uint8_t dst_a, - uint32_t scale, int shift) { - const uint8_t src_channel = (src >> shift) & 0xff; - const uint8_t dst_channel = (dst >> shift) & 0xff; - const uint32_t blend_unscaled = src_channel * src_a + dst_channel * dst_a; - assert(blend_unscaled < (1ULL << 32) / scale); - return (blend_unscaled * scale) >> 24; -} - -// Blend 'src' over 'dst' assuming they are NOT pre-multiplied by alpha. -static uint32_t BlendPixelNonPremult(uint32_t src, uint32_t dst) { - const uint8_t src_a = (src >> 24) & 0xff; - - if (src_a == 0) { - return dst; - } else { - const uint8_t dst_a = (dst >> 24) & 0xff; - // This is the approximate integer arithmetic for the actual formula: - // dst_factor_a = (dst_a * (255 - src_a)) / 255. - const uint8_t dst_factor_a = (dst_a * (256 - src_a)) >> 8; - const uint8_t blend_a = src_a + dst_factor_a; - const uint32_t scale = (1UL << 24) / blend_a; - - const uint8_t blend_r = - BlendChannelNonPremult(src, src_a, dst, dst_factor_a, scale, 0); - const uint8_t blend_g = - BlendChannelNonPremult(src, src_a, dst, dst_factor_a, scale, 8); - const uint8_t blend_b = - BlendChannelNonPremult(src, src_a, dst, dst_factor_a, scale, 16); - assert(src_a + dst_factor_a < 256); - - return (blend_r << 0) | - (blend_g << 8) | - (blend_b << 16) | - ((uint32_t)blend_a << 24); - } -} - -// Blend 'num_pixels' in 'src' over 'dst' assuming they are NOT pre-multiplied -// by alpha. -static void BlendPixelRowNonPremult(uint32_t* const src, - const uint32_t* const dst, int num_pixels) { - int i; - for (i = 0; i < num_pixels; ++i) { - const uint8_t src_alpha = (src[i] >> 24) & 0xff; - if (src_alpha != 0xff) { - src[i] = BlendPixelNonPremult(src[i], dst[i]); - } - } -} - -// Individually multiply each channel in 'pix' by 'scale'. -static WEBP_INLINE uint32_t ChannelwiseMultiply(uint32_t pix, uint32_t scale) { - uint32_t mask = 0x00FF00FF; - uint32_t rb = ((pix & mask) * scale) >> 8; - uint32_t ag = ((pix >> 8) & mask) * scale; - return (rb & mask) | (ag & ~mask); -} - -// Blend 'src' over 'dst' assuming they are pre-multiplied by alpha. -static uint32_t BlendPixelPremult(uint32_t src, uint32_t dst) { - const uint8_t src_a = (src >> 24) & 0xff; - return src + ChannelwiseMultiply(dst, 256 - src_a); -} - -// Blend 'num_pixels' in 'src' over 'dst' assuming they are pre-multiplied by -// alpha. -static void BlendPixelRowPremult(uint32_t* const src, const uint32_t* const dst, - int num_pixels) { - int i; - for (i = 0; i < num_pixels; ++i) { - const uint8_t src_alpha = (src[i] >> 24) & 0xff; - if (src_alpha != 0xff) { - src[i] = BlendPixelPremult(src[i], dst[i]); - } - } -} - -// Returns two ranges (<left, width> pairs) at row 'canvas_y', that belong to -// 'src' but not 'dst'. A point range is empty if the corresponding width is 0. -static void FindBlendRangeAtRow(const WebPIterator* const src, - const WebPIterator* const dst, int canvas_y, - int* const left1, int* const width1, - int* const left2, int* const width2) { - const int src_max_x = src->x_offset + src->width; - const int dst_max_x = dst->x_offset + dst->width; - const int dst_max_y = dst->y_offset + dst->height; - assert(canvas_y >= src->y_offset && canvas_y < (src->y_offset + src->height)); - *left1 = -1; - *width1 = 0; - *left2 = -1; - *width2 = 0; - - if (canvas_y < dst->y_offset || canvas_y >= dst_max_y || - src->x_offset >= dst_max_x || src_max_x <= dst->x_offset) { - *left1 = src->x_offset; - *width1 = src->width; - return; - } - - if (src->x_offset < dst->x_offset) { - *left1 = src->x_offset; - *width1 = dst->x_offset - src->x_offset; - } - - if (src_max_x > dst_max_x) { - *left2 = dst_max_x; - *width2 = src_max_x - dst_max_x; - } -} - -int WebPAnimDecoderGetNext(WebPAnimDecoder* dec, - uint8_t** buf_ptr, int* timestamp_ptr) { - WebPIterator iter; - uint32_t width; - uint32_t height; - int is_key_frame; - int timestamp; - BlendRowFunc blend_row; - - if (dec == NULL || buf_ptr == NULL || timestamp_ptr == NULL) return 0; - if (!WebPAnimDecoderHasMoreFrames(dec)) return 0; - - width = dec->info_.canvas_width; - height = dec->info_.canvas_height; - blend_row = dec->blend_func_; - - // Get compressed frame. - if (!WebPDemuxGetFrame(dec->demux_, dec->next_frame_, &iter)) { - return 0; - } - timestamp = dec->prev_frame_timestamp_ + iter.duration; - - // Initialize. - is_key_frame = IsKeyFrame(&iter, &dec->prev_iter_, - dec->prev_frame_was_keyframe_, width, height); - if (is_key_frame) { - ZeroFillCanvas(dec->curr_frame_, width, height); - } else { - CopyCanvas(dec->prev_frame_disposed_, dec->curr_frame_, width, height); - } - - // Decode. - { - const uint8_t* in = iter.fragment.bytes; - const size_t in_size = iter.fragment.size; - const size_t out_offset = - (iter.y_offset * width + iter.x_offset) * NUM_CHANNELS; - WebPDecoderConfig* const config = &dec->config_; - WebPRGBABuffer* const buf = &config->output.u.RGBA; - buf->stride = NUM_CHANNELS * width; - buf->size = buf->stride * iter.height; - buf->rgba = dec->curr_frame_ + out_offset; - - if (WebPDecode(in, in_size, config) != VP8_STATUS_OK) { - goto Error; - } - } - - // During the decoding of current frame, we may have set some pixels to be - // transparent (i.e. alpha < 255). However, the value of each of these - // pixels should have been determined by blending it against the value of - // that pixel in the previous frame if blending method of is WEBP_MUX_BLEND. - if (iter.frame_num > 1 && iter.blend_method == WEBP_MUX_BLEND && - !is_key_frame) { - if (dec->prev_iter_.dispose_method == WEBP_MUX_DISPOSE_NONE) { - int y; - // Blend transparent pixels with pixels in previous canvas. - for (y = 0; y < iter.height; ++y) { - const size_t offset = - (iter.y_offset + y) * width + iter.x_offset; - blend_row((uint32_t*)dec->curr_frame_ + offset, - (uint32_t*)dec->prev_frame_disposed_ + offset, iter.width); - } - } else { - int y; - assert(dec->prev_iter_.dispose_method == WEBP_MUX_DISPOSE_BACKGROUND); - // We need to blend a transparent pixel with its value just after - // initialization. That is, blend it with: - // * Fully transparent pixel if it belongs to prevRect <-- No-op. - // * The pixel in the previous canvas otherwise <-- Need alpha-blending. - for (y = 0; y < iter.height; ++y) { - const int canvas_y = iter.y_offset + y; - int left1, width1, left2, width2; - FindBlendRangeAtRow(&iter, &dec->prev_iter_, canvas_y, &left1, &width1, - &left2, &width2); - if (width1 > 0) { - const size_t offset1 = canvas_y * width + left1; - blend_row((uint32_t*)dec->curr_frame_ + offset1, - (uint32_t*)dec->prev_frame_disposed_ + offset1, width1); - } - if (width2 > 0) { - const size_t offset2 = canvas_y * width + left2; - blend_row((uint32_t*)dec->curr_frame_ + offset2, - (uint32_t*)dec->prev_frame_disposed_ + offset2, width2); - } - } - } - } - - // Update info of the previous frame and dispose it for the next iteration. - dec->prev_frame_timestamp_ = timestamp; - dec->prev_iter_ = iter; - dec->prev_frame_was_keyframe_ = is_key_frame; - CopyCanvas(dec->curr_frame_, dec->prev_frame_disposed_, width, height); - if (dec->prev_iter_.dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) { - ZeroFillFrameRect(dec->prev_frame_disposed_, width * NUM_CHANNELS, - dec->prev_iter_.x_offset, dec->prev_iter_.y_offset, - dec->prev_iter_.width, dec->prev_iter_.height); - } - ++dec->next_frame_; - - // All OK, fill in the values. - *buf_ptr = dec->curr_frame_; - *timestamp_ptr = timestamp; - return 1; - - Error: - WebPDemuxReleaseIterator(&iter); - return 0; -} - -int WebPAnimDecoderHasMoreFrames(const WebPAnimDecoder* dec) { - if (dec == NULL) return 0; - return (dec->next_frame_ <= (int)dec->info_.frame_count); -} - -void WebPAnimDecoderReset(WebPAnimDecoder* dec) { - if (dec != NULL) { - dec->prev_frame_timestamp_ = 0; - memset(&dec->prev_iter_, 0, sizeof(dec->prev_iter_)); - dec->prev_frame_was_keyframe_ = 0; - dec->next_frame_ = 1; - } -} - -const WebPDemuxer* WebPAnimDecoderGetDemuxer(const WebPAnimDecoder* dec) { - if (dec == NULL) return NULL; - return dec->demux_; -} - -void WebPAnimDecoderDelete(WebPAnimDecoder* dec) { - if (dec != NULL) { - WebPDemuxDelete(dec->demux_); - WebPSafeFree(dec->curr_frame_); - WebPSafeFree(dec->prev_frame_disposed_); - WebPSafeFree(dec); - } -} |