diff --git a/ffmpeg.c b/ffmpeg.c
index c5f73624b2..c8e11be110 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -1172,7 +1172,7 @@ static int output_packet(AVInputStream *ist, int ist_index,
     int data_size, got_picture;
     AVFrame picture;
     void *buffer_to_free;
-    static int samples_size= 0;
+    static unsigned int samples_size= 0;
     static short *samples= NULL;
     AVSubtitle subtitle, *subtitle_to_free;
     int got_subtitle;
diff --git a/libavcodec/4xm.c b/libavcodec/4xm.c
index 107eaf213e..381e8553f6 100644
--- a/libavcodec/4xm.c
+++ b/libavcodec/4xm.c
@@ -123,7 +123,7 @@ typedef struct FourXContext{
     int last_dc;
     DCTELEM __align8 block[6][64];
     uint8_t *bitstream_buffer;
-    int bitstream_buffer_size;
+    unsigned int bitstream_buffer_size;
     CFrameBuffer cfrm[CFRAME_BUFFER_COUNT];
 } FourXContext;
 
diff --git a/libavcodec/asv1.c b/libavcodec/asv1.c
index 222582cd53..99e563ee9f 100644
--- a/libavcodec/asv1.c
+++ b/libavcodec/asv1.c
@@ -48,7 +48,7 @@ typedef struct ASV1Context{
     uint16_t __align8 intra_matrix[64];
     int __align8 q_intra_matrix[64];
     uint8_t *bitstream_buffer;
-    int bitstream_buffer_size;
+    unsigned int bitstream_buffer_size;
 } ASV1Context;
 
 static const uint8_t scantab[64]={
diff --git a/libavcodec/flac.c b/libavcodec/flac.c
index d0efa16b46..97ac53745e 100644
--- a/libavcodec/flac.c
+++ b/libavcodec/flac.c
@@ -66,7 +66,7 @@ typedef struct FLACContext {
     uint8_t *bitstream;
     int bitstream_size;
     int bitstream_index;
-    int allocated_bitstream_size;
+    unsigned int allocated_bitstream_size;
 } FLACContext;
 
 #define METADATA_TYPE_STREAMINFO 0
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 744c0ad0f3..43e349e36b 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -162,7 +162,7 @@ typedef struct H264Context{
 #define NAL_SPS_EXT             13
 #define NAL_AUXILIARY_SLICE     19
     uint8_t *rbsp_buffer;
-    int rbsp_buffer_size;
+    unsigned int rbsp_buffer_size;
 
     /**
       * Used to parse AVC variant of h264
diff --git a/libavcodec/huffyuv.c b/libavcodec/huffyuv.c
index 6233e24310..dc9e123ff4 100644
--- a/libavcodec/huffyuv.c
+++ b/libavcodec/huffyuv.c
@@ -72,7 +72,7 @@ typedef struct HYuvContext{
     VLC vlc[3];
     AVFrame picture;
     uint8_t *bitstream_buffer;
-    int bitstream_buffer_size;
+    unsigned int bitstream_buffer_size;
     DSPContext dsp;
 }HYuvContext;
 
diff --git a/libavcodec/mdec.c b/libavcodec/mdec.c
index daff9499ae..4a346ef609 100644
--- a/libavcodec/mdec.c
+++ b/libavcodec/mdec.c
@@ -49,7 +49,7 @@ typedef struct MDECContext{
     uint16_t __align8 intra_matrix[64];
     int __align8 q_intra_matrix[64];
     uint8_t *bitstream_buffer;
-    int bitstream_buffer_size;
+    unsigned int bitstream_buffer_size;
     int block_last_index[6];
 } MDECContext;
 
diff --git a/libavcodec/mpeg4data.h b/libavcodec/mpeg4data.h
index 586a5871c4..804d2ded89 100644
--- a/libavcodec/mpeg4data.h
+++ b/libavcodec/mpeg4data.h
@@ -169,7 +169,7 @@ static const uint16_t inter_rvlc[170][2]={ //note this is identical to the intra
 {0x3F7C, 15},{0x3F7D, 15},{0x0000, 4}
 };
 
-static const uint8_t inter_rvlc_run[169]={
+static const int8_t inter_rvlc_run[169]={
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  1,  1,  1,  1,  1,
@@ -194,7 +194,7 @@ static const uint8_t inter_rvlc_run[169]={
 43, 44,
 };
 
-static const uint8_t inter_rvlc_level[169]={
+static const int8_t inter_rvlc_level[169]={
  1,  2,  3,  4,  5,  6,  7,  8,
  9, 10, 11, 12, 13, 14, 15, 16,
 17, 18, 19,  1,  2,  3,  4,  5,
@@ -273,7 +273,7 @@ static const uint16_t intra_rvlc[170][2]={
 {0x3F7C, 15},{0x3F7D, 15},{0x0000,  4}
 };
 
-static const uint8_t intra_rvlc_run[169]={
+static const int8_t intra_rvlc_run[169]={
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0,  0,  0,
@@ -298,7 +298,7 @@ static const uint8_t intra_rvlc_run[169]={
 43, 44,
 };
 
-static const uint8_t intra_rvlc_level[169]={
+static const int8_t intra_rvlc_level[169]={
  1,  2,  3,  4,  5,  6,  7,  8,
  9, 10, 11, 12, 13, 14, 15, 16,
 17, 18, 19, 20, 21, 22, 23, 24,
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index d45dbdad41..c1b7024662 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -194,7 +194,7 @@ typedef struct ParseContext{
     uint8_t *buffer;
     int index;
     int last_index;
-    int buffer_size;
+    unsigned int buffer_size;
     uint32_t state;             ///< contains the last few bytes in MSB order
     int frame_start_found;
     int overread;               ///< the number of bytes which where irreversibly read from the next frame
@@ -610,7 +610,7 @@ typedef struct MpegEncContext {
     int divx_packed;
     uint8_t *bitstream_buffer; //Divx 5.01 puts several frames in a single one, this is used to reorder them
     int bitstream_buffer_size;
-    int allocated_bitstream_buffer_size;
+    unsigned int allocated_bitstream_buffer_size;
 
     int xvid_build;
 
diff --git a/libavcodec/shorten.c b/libavcodec/shorten.c
index 22ed3568a8..4d80d40a56 100644
--- a/libavcodec/shorten.c
+++ b/libavcodec/shorten.c
@@ -84,7 +84,7 @@ typedef struct ShortenContext {
     uint8_t *bitstream;
     int bitstream_size;
     int bitstream_index;
-    int allocated_bitstream_size;
+    unsigned int allocated_bitstream_size;
     int header_size;
     uint8_t header[OUT_BUFFER_SIZE];
     int version;
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 5ed508dbce..62ba0d3d45 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -3223,7 +3223,7 @@ int av_read_image(ByteIOContext *pb, const char *filename,
                   AVImageFormat *fmt,
                   int (*alloc_cb)(void *, AVImageInfo *info), void *opaque)
 {
-    char buf[PROBE_BUF_SIZE];
+    uint8_t buf[PROBE_BUF_SIZE];
     AVProbeData probe_data, *pd = &probe_data;
     offset_t pos;
     int ret;