dec/webp.c: don't wait for data before reporting w/h
this partially reverts
f626fe2 Detect canvas and image size mismatch in decoder.
the original change would cause calls to e.g., WebPGetInfo to fail until
a portion of the image chunk was available. With lossy+alpha this meant
waiting for the entire ALPH chunk to be received.
this change restores the original behavior -- reporting the values from
VP8X if available -- while retaining some of the added canvas/image size
checks if the image data is available
Change-Id: I6295b00a2e2d0d4d8847371756af347e4a80bc0e
diff --git a/src/dec/webp.c b/src/dec/webp.c
index 302220f..fda88bd 100644
--- a/src/dec/webp.c
+++ b/src/dec/webp.c
@@ -328,15 +328,19 @@
if (has_animation != NULL) *has_animation = animation_present;
if (format != NULL) *format = 0; // default = undefined
+ image_width = canvas_width;
+ image_height = canvas_height;
if (found_vp8x && (animation_present || fragments_present) &&
headers == NULL) {
- if (width != NULL) *width = canvas_width;
- if (height != NULL) *height = canvas_height;
- return VP8_STATUS_OK; // Just return features from VP8X header.
+ status = VP8_STATUS_OK;
+ goto ReturnWidthHeight; // Just return features from VP8X header.
}
}
- if (data_size < TAG_SIZE) return VP8_STATUS_NOT_ENOUGH_DATA;
+ if (data_size < TAG_SIZE) {
+ status = VP8_STATUS_NOT_ENOUGH_DATA;
+ goto ReturnWidthHeight;
+ }
// Skip over optional chunks if data started with "RIFF + VP8X" or "ALPH".
if ((found_riff && found_vp8x) ||
@@ -344,7 +348,7 @@
status = ParseOptionalChunks(&data, &data_size, hdrs.riff_size,
&hdrs.alpha_data, &hdrs.alpha_data_size);
if (status != VP8_STATUS_OK) {
- return status; // Found an invalid chunk size / insufficient data.
+ goto ReturnWidthHeight; // Invalid chunk size / insufficient data.
}
}
@@ -352,7 +356,7 @@
status = ParseVP8Header(&data, &data_size, hdrs.riff_size,
&hdrs.compressed_size, &hdrs.is_lossless);
if (status != VP8_STATUS_OK) {
- return status; // Wrong VP8/VP8L chunk-header / insufficient data.
+ goto ReturnWidthHeight; // Wrong VP8/VP8L chunk-header / insufficient data.
}
if (hdrs.compressed_size > MAX_CHUNK_PAYLOAD) {
return VP8_STATUS_BITSTREAM_ERROR;
@@ -364,7 +368,8 @@
if (!hdrs.is_lossless) {
if (data_size < VP8_FRAME_HEADER_SIZE) {
- return VP8_STATUS_NOT_ENOUGH_DATA;
+ status = VP8_STATUS_NOT_ENOUGH_DATA;
+ goto ReturnWidthHeight;
}
// Validates raw VP8 data.
if (!VP8GetInfo(data, data_size, (uint32_t)hdrs.compressed_size,
@@ -373,7 +378,8 @@
}
} else {
if (data_size < VP8L_FRAME_HEADER_SIZE) {
- return VP8_STATUS_NOT_ENOUGH_DATA;
+ status = VP8_STATUS_NOT_ENOUGH_DATA;
+ goto ReturnWidthHeight;
}
// Validates raw VP8L data.
if (!VP8LGetInfo(data, data_size, &image_width, &image_height, has_alpha)) {
@@ -386,20 +392,26 @@
return VP8_STATUS_BITSTREAM_ERROR;
}
}
- if (width != NULL) *width = image_width;
- if (height != NULL) *height = image_height;
- if (has_alpha != NULL) {
- // If the data did not contain a VP8X/VP8L chunk the only definitive way
- // to set this is by looking for alpha data (from an ALPH chunk).
- *has_alpha |= (hdrs.alpha_data != NULL);
- }
if (headers != NULL) {
*headers = hdrs;
headers->offset = data - headers->data;
assert((uint64_t)(data - headers->data) < MAX_CHUNK_PAYLOAD);
assert(headers->offset == headers->data_size - data_size);
}
- return VP8_STATUS_OK; // Return features from VP8 header.
+ ReturnWidthHeight:
+ if (status == VP8_STATUS_OK ||
+ (status == VP8_STATUS_NOT_ENOUGH_DATA && found_vp8x && headers == NULL)) {
+ if (has_alpha != NULL) {
+ // If the data did not contain a VP8X/VP8L chunk the only definitive way
+ // to set this is by looking for alpha data (from an ALPH chunk).
+ *has_alpha |= (hdrs.alpha_data != NULL);
+ }
+ if (width != NULL) *width = image_width;
+ if (height != NULL) *height = image_height;
+ return VP8_STATUS_OK;
+ } else {
+ return status;
+ }
}
VP8StatusCode WebPParseHeaders(WebPHeaderStructure* const headers) {
