cscg24-guacamole

CSCG 2024 Challenge 'Guacamole Mashup'
git clone https://git.sinitax.com/sinitax/cscg24-guacamole
Log | Files | Refs | sfeed.txt

webp.c (2333B)

      1/*
      2 * Licensed to the Apache Software Foundation (ASF) under one
      3 * or more contributor license agreements.  See the NOTICE file
      4 * distributed with this work for additional information
      5 * regarding copyright ownership.  The ASF licenses this file
      6 * to you under the Apache License, Version 2.0 (the
      7 * "License"); you may not use this file except in compliance
      8 * with the License.  You may obtain a copy of the License at
      9 *
     10 *   http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing,
     13 * software distributed under the License is distributed on an
     14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
     15 * KIND, either express or implied.  See the License for the
     16 * specific language governing permissions and limitations
     17 * under the License.
     18 */
     19
     20#include "config.h"
     21#include "log.h"
     22#include "webp.h"
     23
     24#include <cairo/cairo.h>
     25#include <guacamole/client.h>
     26#include <webp/decode.h>
     27
     28#include <stdint.h>
     29#include <stdlib.h>
     30
     31cairo_surface_t* guacenc_webp_decoder(unsigned char* data, int length) {
     32
     33    int width, height;
     34
     35    /* Validate WebP and pull dimensions */
     36    if (!WebPGetInfo((uint8_t*) data, length, &width, &height)) {
     37        guacenc_log(GUAC_LOG_WARNING, "Invalid WebP data");
     38        return NULL;
     39    }
     40
     41    /* Create blank Cairo surface */
     42    cairo_surface_t* surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
     43            width, height);
     44
     45    /* Fill surface with opaque black */
     46    cairo_t* cairo = cairo_create(surface);
     47    cairo_set_operator(cairo, CAIRO_OPERATOR_SOURCE);
     48    cairo_set_source_rgba(cairo, 0.0, 0.0, 0.0, 1.0);
     49    cairo_paint(cairo);
     50    cairo_destroy(cairo);
     51
     52    /* Finish any pending draws */
     53    cairo_surface_flush(surface);
     54
     55    /* Pull underlying buffer and its stride */
     56    int stride = cairo_image_surface_get_stride(surface);
     57    unsigned char* image = cairo_image_surface_get_data(surface);
     58
     59    /* Read WebP into surface */
     60    uint8_t* result = WebPDecodeBGRAInto((uint8_t*) data, length,
     61            (uint8_t*) image, stride * height, stride);
     62
     63    /* Verify WebP was successfully decoded */
     64    if (result == NULL) {
     65        guacenc_log(GUAC_LOG_WARNING, "Invalid WebP data");
     66        cairo_surface_destroy(surface);
     67        return NULL;
     68    }
     69
     70    /* WebP was read successfully */
     71    return surface;
     72
     73}
     74