VP8StatusCode DecodeWebPIncremental(
const uint8_t* const data, size_t data_size,
int verbose, WebPDecoderConfig* const config) {
Stopwatch stop_watch;
VP8StatusCode status = VP8_STATUS_OK;
if (config == NULL) return VP8_STATUS_INVALID_PARAM;
PrintAnimationWarning(config);
StopwatchReset(&stop_watch);
// Decoding call.
{
WebPIDecoder* const idec = WebPIDecode(data, data_size, config);
if (idec == NULL) {
fprintf(stderr, "Failed during WebPINewDecoder().\n");
return VP8_STATUS_OUT_OF_MEMORY;
} else {
#ifdef WEBP_EXPERIMENTAL_FEATURES
size_t size = 0;
const size_t incr = 2 + (data_size / 20);
while (size < data_size) {
size_t next_size = size + (rand() % incr);
if (next_size > data_size) next_size = data_size;
status = WebPIUpdate(idec, data, next_size);
if (status != VP8_STATUS_OK && status != VP8_STATUS_SUSPENDED) break;
size = next_size;
}
#else
status = WebPIUpdate(idec, data, data_size);
#endif
WebPIDelete(idec);
}
}
if (verbose) {
const double decode_time = StopwatchReadAndReset(&stop_watch);
fprintf(stderr, "Time to decode picture: %.3fs\n", decode_time);
}
return status;
}
static int
WEBPDecode(WEBPDec* pSrc, Vbitmap *vbitmap,
YmagineFormatOptions *options)
{
int contentSize;
int origWidth = 0;
int origHeight = 0;
int quality;
unsigned char header[WEBP_HEADER_SIZE + 32];
int headerlen;
int toRead;
unsigned char *input = NULL;
int inputlen;
int oformat;
int opitch;
unsigned char *odata;
int rc;
Vrect srcrect;
Vrect destrect;
WebPIDecoder* idec;
if (options == NULL) {
/* Options argument is mandatory */
return 0;
}
headerlen = YchannelRead(pSrc->channel, (char *) header, sizeof(header));
if (headerlen < WEBP_HEADER_SIZE) {
return 0;
}
/* Check WEBP header */
contentSize = WebpCheckHeader((const char*) header, headerlen);
if (contentSize <= 0) {
return 0;
}
if (WebPGetInfo(header, headerlen, &origWidth, &origHeight) == 0) {
ALOGD("invalid VP8 header");
return 0;
}
if (origWidth <= 0 || origHeight <= 0) {
return 0;
}
if (YmagineFormatOptions_invokeCallback(options, YMAGINE_IMAGEFORMAT_WEBP,
origWidth, origHeight) != YMAGINE_OK) {
return 0;
}
if (YmaginePrepareTransform(vbitmap, options,
origWidth, origHeight,
&srcrect, &destrect) != YMAGINE_OK) {
return 0;
}
#if YMAGINE_DEBUG_WEBP
ALOGD("size: %dx%d req: %dx%d %s -> output: %dx%d",
origWidth, origHeight,
destrect.width, destrect.height,
(options->scalemode == YMAGINE_SCALE_CROP) ? "crop" :
(options->scalemode == YMAGINE_SCALE_FIT ? "fit" : "letterbox"),
destrect.width, destrect.height);
#endif
if (vbitmap != NULL) {
if (options->resizable) {
destrect.x = 0;
destrect.y = 0;
if (VbitmapResize(vbitmap, destrect.width, destrect.height) != YMAGINE_OK) {
return 0;
}
}
if (VbitmapType(vbitmap) == VBITMAP_NONE) {
/* Decode bounds only, return positive number (number of lines) on success */
return VbitmapHeight(vbitmap);
}
}
pSrc->bitmap = vbitmap;
inputlen = contentSize;
toRead = inputlen - headerlen;
rc = VbitmapLock(vbitmap);
if (rc != YMAGINE_OK) {
ALOGE("VbitmapLock() failed (code %d)", rc);
rc = YMAGINE_ERROR;
} else {
odata = VbitmapBuffer(vbitmap);
opitch = VbitmapPitch(vbitmap);
oformat = VbitmapColormode(vbitmap);
pSrc->inwidth = origWidth;
pSrc->inheight = origHeight;
pSrc->outwidth = destrect.width;
pSrc->outheight = destrect.height;
if (odata == NULL) {
ALOGD("failed to get reference to pixel buffer");
rc = YMAGINE_ERROR;
} else {
WebPDecoderConfig config;
int supported = 1;
int webpcolorspace;
switch(oformat) {
case VBITMAP_COLOR_RGBA:
webpcolorspace = MODE_RGBA;
break;
case VBITMAP_COLOR_RGB:
webpcolorspace = MODE_RGB;
break;
case VBITMAP_COLOR_rgbA:
webpcolorspace = MODE_rgbA;
break;
case VBITMAP_COLOR_ARGB:
webpcolorspace = MODE_ARGB;
break;
case VBITMAP_COLOR_Argb:
webpcolorspace = MODE_Argb;
break;
case VBITMAP_COLOR_GRAYSCALE:
case VBITMAP_COLOR_YUV:
case VBITMAP_COLOR_CMYK:
case VBITMAP_COLOR_YCbCr:
default:
supported = 0;
break;
}
if (!supported) {
ALOGD("currently only support RGB, RGBA webp decoding");
rc = YMAGINE_ERROR;
} else {
pSrc->isdirect = 1;
pSrc->outformat = oformat;
pSrc->outbpp = VbitmapBpp(vbitmap);
pSrc->outstride = opitch;
pSrc->outbuffer = odata + destrect.x * pSrc->outbpp + destrect.y * pSrc->outstride;
WebPInitDecoderConfig(&config);
quality = YmagineFormatOptions_normalizeQuality(options);
if (quality < 90) {
config.options.no_fancy_upsampling = 1;
}
if (quality < 60) {
config.options.bypass_filtering = 1;
}
config.options.use_threads = 1;
if (srcrect.x != 0 || srcrect.y != 0 || srcrect.width != origWidth || srcrect.height != origHeight) {
/* Crop on source */
config.options.use_cropping = 1;
config.options.crop_left = srcrect.x;
config.options.crop_top = srcrect.y;
config.options.crop_width = srcrect.width;
config.options.crop_height = srcrect.height;
}
if (pSrc->outwidth != pSrc->inwidth || pSrc->outheight != pSrc->inheight) {
config.options.use_scaling = 1;
config.options.scaled_width = pSrc->outwidth;
config.options.scaled_height = pSrc->outheight;
}
rc = YMAGINE_ERROR;
// Specify the desired output colorspace:
config.output.colorspace = webpcolorspace;
// Have config.output point to an external buffer:
config.output.u.RGBA.rgba = (uint8_t*) pSrc->outbuffer;
config.output.u.RGBA.stride = pSrc->outstride;
config.output.u.RGBA.size = pSrc->outstride * pSrc->outheight;
config.output.is_external_memory = 1;
idec = WebPIDecode(NULL, 0, &config);
if (idec != NULL) {
VP8StatusCode status;
status = WebPIAppend(idec, header, headerlen);
if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
int bytes_remaining = toRead;
int bytes_read;
int bytes_req;
unsigned char rbuf[8192];
// See WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
bytes_req = sizeof(rbuf);
while (bytes_remaining > 0) {
if (bytes_req > bytes_remaining) {
bytes_req = bytes_remaining;
}
bytes_read = YchannelRead(pSrc->channel, rbuf, bytes_req);
if (bytes_read <= 0) {
break;
}
status = WebPIAppend(idec, (uint8_t*) rbuf, bytes_read);
if (status == VP8_STATUS_OK) {
rc = YMAGINE_OK;
break;
} else if (status == VP8_STATUS_SUSPENDED) {
if (bytes_remaining > 0) {
bytes_remaining -= bytes_read;
}
} else {
/* error */
break;
}
// The above call decodes the current available buffer.
// Part of the image can now be refreshed by calling
// WebPIDecGetRGB()/WebPIDecGetYUVA() etc.
}
}
}
// the object doesn't own the image memory, so it can now be deleted.
WebPIDelete(idec);
WebPFreeDecBuffer(&config.output);
}
}
VbitmapUnlock(vbitmap);
}
if (input) {
Ymem_free((char*) input);
}
if (!pSrc->isdirect) {
Ymem_free(pSrc->outbuffer);
}
if (rc == YMAGINE_OK) {
return origHeight;
}
return 0;
}
