4 files changed, 13 insertions, 15 deletions

diff --git a/thirdparty/libwebp/src/mux/anim_encode.c b/thirdparty/libwebp/src/mux/anim_encode.c
index 7be99068f6..7078d9ae6b 100644
--- a/thirdparty/libwebp/src/mux/anim_encode.c
+++ b/thirdparty/libwebp/src/mux/anim_encode.c
@@ -248,9 +248,6 @@ WebPAnimEncoder* WebPAnimEncoderNewInternal(
 
   enc = (WebPAnimEncoder*)WebPSafeCalloc(1, sizeof(*enc));
   if (enc == NULL) return NULL;
-  // sanity inits, so we can call WebPAnimEncoderDelete():
-  enc->encoded_frames_ = NULL;
-  enc->mux_ = NULL;
   MarkNoError(enc);
 
   // Dimensions and options.
@@ -421,7 +418,7 @@ static void MinimizeChangeRectangle(const WebPPicture* const src,
   const int max_allowed_diff_lossy = QualityToMaxDiff(quality);
   const int max_allowed_diff = is_lossless ? 0 : max_allowed_diff_lossy;
 
-  // Sanity checks.
+  // Assumption/correctness checks.
   assert(src->width == dst->width && src->height == dst->height);
   assert(rect->x_offset_ + rect->width_ <= dst->width);
   assert(rect->y_offset_ + rect->height_ <= dst->height);
@@ -949,7 +946,8 @@ static int IncreasePreviousDuration(WebPAnimEncoder* const enc, int duration) {
   int new_duration;
 
   assert(enc->count_ >= 1);
-  assert(prev_enc_frame->sub_frame_.duration ==
+  assert(!prev_enc_frame->is_key_frame_ ||
+         prev_enc_frame->sub_frame_.duration ==
          prev_enc_frame->key_frame_.duration);
   assert(prev_enc_frame->sub_frame_.duration ==
          (prev_enc_frame->sub_frame_.duration & (MAX_DURATION - 1)));
@@ -966,7 +964,7 @@ static int IncreasePreviousDuration(WebPAnimEncoder* const enc, int duration) {
       0x10, 0x88, 0x88, 0x08
     };
     const WebPData lossless_1x1 = {
-        lossless_1x1_bytes, sizeof(lossless_1x1_bytes)
+      lossless_1x1_bytes, sizeof(lossless_1x1_bytes)
     };
     const uint8_t lossy_1x1_bytes[] = {
       0x52, 0x49, 0x46, 0x46, 0x40, 0x00, 0x00, 0x00, 0x57, 0x45, 0x42, 0x50,
@@ -1358,6 +1356,12 @@ int WebPAnimEncoderAdd(WebPAnimEncoder* enc, WebPPicture* frame, int timestamp,
     if (!IncreasePreviousDuration(enc, (int)prev_frame_duration)) {
       return 0;
     }
+    // IncreasePreviousDuration() may add a frame to avoid exceeding
+    // MAX_DURATION which could cause CacheFrame() to over read encoded_frames_
+    // before the next flush.
+    if (enc->count_ == enc->size_ && !FlushFrames(enc)) {
+      return 0;
+    }
   } else {
     enc->first_timestamp_ = timestamp;
   }
diff --git a/thirdparty/libwebp/src/mux/muxedit.c b/thirdparty/libwebp/src/mux/muxedit.c
index ccf14b2a0c..02c3edecd7 100644
--- a/thirdparty/libwebp/src/mux/muxedit.c
+++ b/thirdparty/libwebp/src/mux/muxedit.c
@@ -235,7 +235,6 @@ WebPMuxError WebPMuxSetImage(WebPMux* mux, const WebPData* bitstream,
   WebPMuxImage wpi;
   WebPMuxError err;
 
-  // Sanity checks.
   if (mux == NULL || bitstream == NULL || bitstream->bytes == NULL ||
       bitstream->size > MAX_CHUNK_PAYLOAD) {
     return WEBP_MUX_INVALID_ARGUMENT;
@@ -267,7 +266,6 @@ WebPMuxError WebPMuxPushFrame(WebPMux* mux, const WebPMuxFrameInfo* info,
   WebPMuxImage wpi;
   WebPMuxError err;
 
-  // Sanity checks.
   if (mux == NULL || info == NULL) return WEBP_MUX_INVALID_ARGUMENT;
 
   if (info->id != WEBP_CHUNK_ANMF) return WEBP_MUX_INVALID_ARGUMENT;
diff --git a/thirdparty/libwebp/src/mux/muxi.h b/thirdparty/libwebp/src/mux/muxi.h
index ad3e1bdb97..330da66754 100644
--- a/thirdparty/libwebp/src/mux/muxi.h
+++ b/thirdparty/libwebp/src/mux/muxi.h
@@ -28,8 +28,8 @@ extern "C" {
 // Defines and constants.
 
 #define MUX_MAJ_VERSION 1
-#define MUX_MIN_VERSION 1
-#define MUX_REV_VERSION 0
+#define MUX_MIN_VERSION 2
+#define MUX_REV_VERSION 1
 
 // Chunk object.
 typedef struct WebPChunk WebPChunk;
diff --git a/thirdparty/libwebp/src/mux/muxread.c b/thirdparty/libwebp/src/mux/muxread.c
index ae3b876bc5..80050396e1 100644
--- a/thirdparty/libwebp/src/mux/muxread.c
+++ b/thirdparty/libwebp/src/mux/muxread.c
@@ -56,7 +56,7 @@ static WebPMuxError ChunkVerifyAndAssign(WebPChunk* chunk,
   uint32_t chunk_size;
   WebPData chunk_data;
 
-  // Sanity checks.
+  // Correctness checks.
   if (data_size < CHUNK_HEADER_SIZE) return WEBP_MUX_NOT_ENOUGH_DATA;
   chunk_size = GetLE32(data + TAG_SIZE);
   if (chunk_size > MAX_CHUNK_PAYLOAD) return WEBP_MUX_BAD_DATA;
@@ -155,7 +155,6 @@ static int MuxImageParse(const WebPChunk* const chunk, int copy_data,
         break;
       default:
         goto Fail;
-        break;
     }
     subchunk_size = ChunkDiskSize(&subchunk);
     bytes += subchunk_size;
@@ -187,7 +186,6 @@ WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
   WebPChunk** chunk_list_ends[WEBP_CHUNK_NIL + 1] = { NULL };
   ChunkInit(&chunk);
 
-  // Sanity checks.
   if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_MUX_ABI_VERSION)) {
     return NULL;  // version mismatch
   }
@@ -264,7 +262,6 @@ WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
         if (!MuxImageParse(&chunk, copy_data, wpi)) goto Err;
         ChunkRelease(&chunk);
         goto PushImage;
-        break;
       default:  // A non-image chunk.
         if (wpi->is_partial_) goto Err;  // Encountered a non-image chunk before
                                          // getting all chunks of an image.
@@ -483,7 +480,6 @@ WebPMuxError WebPMuxGetFrame(
   WebPMuxError err;
   WebPMuxImage* wpi;
 
-  // Sanity checks.
   if (mux == NULL || frame == NULL) {
     return WEBP_MUX_INVALID_ARGUMENT;
   }