diff --git a/test/encode_api_test.cc b/test/encode_api_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a7200e653a0d63fa10d00a5151bab5df81c7bd9b
--- /dev/null
+++ b/test/encode_api_test.cc
@@ -0,0 +1,68 @@
+/*
+ *  Copyright (c) 2016 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE 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.
+ */
+
+#include "third_party/googletest/src/include/gtest/gtest.h"
+
+#include "./vpx_config.h"
+#include "vpx/vp8cx.h"
+#include "vpx/vpx_encoder.h"
+
+namespace {
+
+#define NELEMENTS(x) static_cast<int>(sizeof(x) / sizeof(x[0]))
+
+TEST(EncodeAPI, InvalidParams) {
+  static const vpx_codec_iface_t *kCodecs[] = {
+#if CONFIG_VP8_ENCODER
+    &vpx_codec_vp8_cx_algo,
+#endif
+#if CONFIG_VP9_ENCODER
+    &vpx_codec_vp9_cx_algo,
+#endif
+#if CONFIG_VP10_ENCODER
+    &vpx_codec_vp10_cx_algo,
+#endif
+  };
+  uint8_t buf[1] = {0};
+  vpx_image_t img;
+  vpx_codec_ctx_t enc;
+  vpx_codec_enc_cfg_t cfg;
+
+  EXPECT_EQ(&img, vpx_img_wrap(&img, VPX_IMG_FMT_I420, 1, 1, 1, buf));
+
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM, vpx_codec_enc_init(NULL, NULL, NULL, 0));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM, vpx_codec_enc_init(&enc, NULL, NULL, 0));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM, vpx_codec_encode(NULL, NULL, 0, 0, 0, 0));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM, vpx_codec_encode(NULL, &img, 0, 0, 0, 0));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM, vpx_codec_destroy(NULL));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM,
+            vpx_codec_enc_config_default(NULL, NULL, 0));
+  EXPECT_EQ(VPX_CODEC_INVALID_PARAM,
+            vpx_codec_enc_config_default(NULL, &cfg, 0));
+  EXPECT_TRUE(vpx_codec_error(NULL) != NULL);
+
+  for (int i = 0; i < NELEMENTS(kCodecs); ++i) {
+    SCOPED_TRACE(vpx_codec_iface_name(kCodecs[i]));
+    EXPECT_EQ(VPX_CODEC_INVALID_PARAM,
+              vpx_codec_enc_init(NULL, kCodecs[i], NULL, 0));
+    EXPECT_EQ(VPX_CODEC_INVALID_PARAM,
+              vpx_codec_enc_init(&enc, kCodecs[i], NULL, 0));
+    EXPECT_EQ(VPX_CODEC_INVALID_PARAM,
+              vpx_codec_enc_config_default(kCodecs[i], &cfg, 1));
+
+    EXPECT_EQ(VPX_CODEC_OK, vpx_codec_enc_config_default(kCodecs[i], &cfg, 0));
+    EXPECT_EQ(VPX_CODEC_OK, vpx_codec_enc_init(&enc, kCodecs[i], &cfg, 0));
+    EXPECT_EQ(VPX_CODEC_OK, vpx_codec_encode(&enc, NULL, 0, 0, 0, 0));
+
+    EXPECT_EQ(VPX_CODEC_OK, vpx_codec_destroy(&enc));
+  }
+}
+
+}  // namespace
diff --git a/test/test.mk b/test/test.mk
index 80b57e505b4c3053f6631f953ff0cce1f061c474..e8e830489b66837b58df4f074e4942ec484df744 100644
--- a/test/test.mk
+++ b/test/test.mk
@@ -20,6 +20,7 @@ LIBVPX_TEST_SRCS-$(CONFIG_DECODERS)    += ivf_video_source.h
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += ../y4minput.h ../y4minput.c
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += aq_segment_test.cc
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += datarate_test.cc
+LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += encode_api_test.cc
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += error_resilience_test.cc
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += i420_video_source.h
 LIBVPX_TEST_SRCS-$(CONFIG_ENCODERS)    += resize_test.cc
diff --git a/vp10/encoder/lookahead.c b/vp10/encoder/lookahead.c
index 431c631759f370aa595c6b60f62e24a3d57af9ca..dce0139038527c24fcd035546ef70566298b3e43 100644
--- a/vp10/encoder/lookahead.c
+++ b/vp10/encoder/lookahead.c
@@ -207,7 +207,7 @@ struct lookahead_entry *vp10_lookahead_pop(struct lookahead_ctx *ctx,
                                           int drain) {
   struct lookahead_entry *buf = NULL;
 
-  if (ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
+  if (ctx && ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
     buf = pop(ctx, &ctx->read_idx);
     ctx->sz--;
   }
diff --git a/vp8/encoder/lookahead.c b/vp8/encoder/lookahead.c
index ce2ce08c170e17c2722f3558fde2934d5c0214de..66233857433f11e811a630be1f76cb8a3d73ee77 100644
--- a/vp8/encoder/lookahead.c
+++ b/vp8/encoder/lookahead.c
@@ -181,6 +181,7 @@ vp8_lookahead_pop(struct lookahead_ctx *ctx,
 {
     struct lookahead_entry* buf = NULL;
 
+    assert(ctx != NULL);
     if(ctx->sz && (drain || ctx->sz == ctx->max_sz - 1))
     {
         buf = pop(ctx, &ctx->read_idx);
diff --git a/vp9/encoder/vp9_lookahead.c b/vp9/encoder/vp9_lookahead.c
index 8787be8ee60c19478c99762f27658ff9a9bd8fb6..def9b8c1db0e9cad44d0f786d1413c92a374af5c 100644
--- a/vp9/encoder/vp9_lookahead.c
+++ b/vp9/encoder/vp9_lookahead.c
@@ -207,7 +207,7 @@ struct lookahead_entry *vp9_lookahead_pop(struct lookahead_ctx *ctx,
                                           int drain) {
   struct lookahead_entry *buf = NULL;
 
-  if (ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
+  if (ctx && ctx->sz && (drain || ctx->sz == ctx->max_sz - MAX_PRE_FRAMES)) {
     buf = pop(ctx, &ctx->read_idx);
     ctx->sz--;
   }