interplayvideo: convert to bytestream2.

1 files changed, 124 insertions, 199 deletions

diff --git a/libavcodec/interplayvideo.c b/libavcodec/interplayvideo.c
index 4a250a8f19..256b6c65b1 100644
--- a/libavcodec/interplayvideo.c
+++ b/libavcodec/interplayvideo.c
@@ -56,14 +56,8 @@ typedef struct IpvideoContext {
     const unsigned char *decoding_map;
     int decoding_map_size;
 
-    const unsigned char *buf;
-    int size;
-
     int is_16bpp;
-    const unsigned char *stream_ptr;
-    const unsigned char *stream_end;
-    const uint8_t *mv_ptr;
-    const uint8_t *mv_end;
+    GetByteContext stream_ptr, mv_ptr;
     unsigned char *pixel_ptr;
     int line_inc;
     int stride;
@@ -72,13 +66,6 @@ typedef struct IpvideoContext {
     uint32_t pal[256];
 } IpvideoContext;
 
-#define CHECK_STREAM_PTR(stream_ptr, stream_end, n) \
-    if (stream_end - stream_ptr < n) { \
-        av_log(s->avctx, AV_LOG_ERROR, "Interplay video warning: stream_ptr out of bounds (%p >= %p)\n", \
-               stream_ptr + n, stream_end); \
-        return -1; \
-    }
-
 static int copy_from(IpvideoContext *s, AVFrame *src, int delta_x, int delta_y)
 {
     int current_offset = s->pixel_ptr - s->current_frame.data[0];
@@ -118,11 +105,9 @@ static int ipvideo_decode_block_opcode_0x2(IpvideoContext *s)
 
     /* copy block from 2 frames ago using a motion vector; need 1 more byte */
     if (!s->is_16bpp) {
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
-        B = *s->stream_ptr++;
+        B = bytestream2_get_byte(&s->stream_ptr);
     } else {
-        CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
-        B = *s->mv_ptr++;
+        B = bytestream2_get_byte(&s->mv_ptr);
     }
 
     if (B < 56) {
@@ -146,11 +131,9 @@ static int ipvideo_decode_block_opcode_0x3(IpvideoContext *s)
 
     /* need 1 more byte for motion */
     if (!s->is_16bpp) {
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
-        B = *s->stream_ptr++;
+        B = bytestream2_get_byte(&s->stream_ptr);
     } else {
-        CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
-        B = *s->mv_ptr++;
+        B = bytestream2_get_byte(&s->mv_ptr);
     }
 
     if (B < 56) {
@@ -172,11 +155,9 @@ static int ipvideo_decode_block_opcode_0x4(IpvideoContext *s)
 
     /* copy a block from the previous frame; need 1 more byte */
     if (!s->is_16bpp) {
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
-        B = *s->stream_ptr++;
+        B = bytestream2_get_byte(&s->stream_ptr);
     } else {
-        CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
-        B = *s->mv_ptr++;
+        B = bytestream2_get_byte(&s->mv_ptr);
     }
 
     BL = B & 0x0F;
@@ -194,10 +175,8 @@ static int ipvideo_decode_block_opcode_0x5(IpvideoContext *s)
 
     /* copy a block from the previous frame using an expanded range;
      * need 2 more bytes */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-    x = *s->stream_ptr++;
-    y = *s->stream_ptr++;
+    x = bytestream2_get_byte(&s->stream_ptr);
+    y = bytestream2_get_byte(&s->stream_ptr);
 
     av_dlog(NULL, "    motion bytes = %d, %d\n", x, y);
     return copy_from(s, &s->last_frame, x, y);
@@ -219,18 +198,14 @@ static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
     unsigned int flags;
 
     /* 2-color encoding */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-    P[0] = *s->stream_ptr++;
-    P[1] = *s->stream_ptr++;
+    P[0] = bytestream2_get_byte(&s->stream_ptr);
+    P[1] = bytestream2_get_byte(&s->stream_ptr);
 
     if (P[0] <= P[1]) {
 
         /* need 8 more bytes from the stream */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
         for (y = 0; y < 8; y++) {
-            flags = *s->stream_ptr++ | 0x100;
+            flags = bytestream2_get_byte(&s->stream_ptr) | 0x100;
             for (; flags != 1; flags >>= 1)
                 *s->pixel_ptr++ = P[flags & 1];
             s->pixel_ptr += s->line_inc;
@@ -239,9 +214,7 @@ static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
     } else {
 
         /* need 2 more bytes from the stream */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-        flags = bytestream_get_le16(&s->stream_ptr);
+        flags = bytestream2_get_le16(&s->stream_ptr);
         for (y = 0; y < 8; y += 2) {
             for (x = 0; x < 8; x += 2, flags >>= 1) {
                 s->pixel_ptr[x                ] =
@@ -260,26 +233,23 @@ static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
 static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
 {
     int x, y;
-    unsigned char P[2];
+    unsigned char P[4];
     unsigned int flags = 0;
 
     /* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
      * either top and bottom or left and right halves */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-    P[0] = *s->stream_ptr++;
-    P[1] = *s->stream_ptr++;
+    P[0] = bytestream2_get_byte(&s->stream_ptr);
+    P[1] = bytestream2_get_byte(&s->stream_ptr);
 
     if (P[0] <= P[1]) {
-
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 14);
-        s->stream_ptr -= 2;
-
         for (y = 0; y < 16; y++) {
             // new values for each 4x4 block
             if (!(y & 3)) {
-                P[0] = *s->stream_ptr++; P[1] = *s->stream_ptr++;
-                flags = bytestream_get_le16(&s->stream_ptr);
+                if (y) {
+                    P[0]  = bytestream2_get_byte(&s->stream_ptr);
+                    P[1]  = bytestream2_get_byte(&s->stream_ptr);
+                }
+                flags = bytestream2_get_le16(&s->stream_ptr);
             }
 
             for (x = 0; x < 4; x++, flags >>= 1)
@@ -290,13 +260,11 @@ static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
         }
 
     } else {
+        flags = bytestream2_get_le32(&s->stream_ptr);
+        P[2] = bytestream2_get_byte(&s->stream_ptr);
+        P[3] = bytestream2_get_byte(&s->stream_ptr);
 
-        /* need 10 more bytes */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 10);
-
-        if (s->stream_ptr[4] <= s->stream_ptr[5]) {
-
-            flags = bytestream_get_le32(&s->stream_ptr);
+        if (P[2] <= P[3]) {
 
             /* vertical split; left & right halves are 2-color encoded */
 
@@ -307,8 +275,9 @@ static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
                 // switch to right half
                 if (y == 7) {
                     s->pixel_ptr -= 8 * s->stride - 4;
-                    P[0] = *s->stream_ptr++; P[1] = *s->stream_ptr++;
-                    flags = bytestream_get_le32(&s->stream_ptr);
+                    P[0]  = P[2];
+                    P[1]  = P[3];
+                    flags = bytestream2_get_le32(&s->stream_ptr);
                 }
             }
 
@@ -318,12 +287,12 @@ static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
 
             for (y = 0; y < 8; y++) {
                 if (y == 4) {
-                    P[0] = *s->stream_ptr++;
-                    P[1] = *s->stream_ptr++;
+                    P[0]  = P[2];
+                    P[1]  = P[3];
+                    flags = bytestream2_get_le32(&s->stream_ptr);
                 }
-                flags = *s->stream_ptr++ | 0x100;
 
-                for (; flags != 1; flags >>= 1)
+                for (x = 0; x < 8; x++, flags >>= 1)
                     *s->pixel_ptr++ = P[flags & 1];
                 s->pixel_ptr += s->line_inc;
             }
@@ -340,20 +309,15 @@ static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
     unsigned char P[4];
 
     /* 4-color encoding */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
-    memcpy(P, s->stream_ptr, 4);
-    s->stream_ptr += 4;
+    bytestream2_get_buffer(&s->stream_ptr, P, 4);
 
     if (P[0] <= P[1]) {
         if (P[2] <= P[3]) {
 
             /* 1 of 4 colors for each pixel, need 16 more bytes */
-            CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
-
             for (y = 0; y < 8; y++) {
                 /* get the next set of 8 2-bit flags */
-                int flags = bytestream_get_le16(&s->stream_ptr);
+                int flags = bytestream2_get_le16(&s->stream_ptr);
                 for (x = 0; x < 8; x++, flags >>= 2)
                     *s->pixel_ptr++ = P[flags & 0x03];
                 s->pixel_ptr += s->line_inc;
@@ -363,9 +327,7 @@ static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
             uint32_t flags;
 
             /* 1 of 4 colors for each 2x2 block, need 4 more bytes */
-            CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
-            flags = bytestream_get_le32(&s->stream_ptr);
+            flags = bytestream2_get_le32(&s->stream_ptr);
 
             for (y = 0; y < 8; y += 2) {
                 for (x = 0; x < 8; x += 2, flags >>= 2) {
@@ -382,9 +344,7 @@ static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
         uint64_t flags;
 
         /* 1 of 4 colors for each 2x1 or 1x2 block, need 8 more bytes */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
-        flags = bytestream_get_le64(&s->stream_ptr);
+        flags = bytestream2_get_le64(&s->stream_ptr);
         if (P[2] <= P[3]) {
             for (y = 0; y < 8; y++) {
                 for (x = 0; x < 8; x += 2, flags >>= 2) {
@@ -411,24 +371,21 @@ static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
 static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
 {
     int x, y;
-    unsigned char P[4];
+    unsigned char P[8];
     int flags = 0;
 
+    bytestream2_get_buffer(&s->stream_ptr, P, 4);
+
     /* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
      * either top and bottom or left and right halves */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
-
-    if (s->stream_ptr[0] <= s->stream_ptr[1]) {
+    if (P[0] <= P[1]) {
 
         /* 4-color encoding for each quadrant; need 32 bytes */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 32);
-
         for (y = 0; y < 16; y++) {
             // new values for each 4x4 block
             if (!(y & 3)) {
-                memcpy(P, s->stream_ptr, 4);
-                s->stream_ptr += 4;
-                flags = bytestream_get_le32(&s->stream_ptr);
+                if (y) bytestream2_get_buffer(&s->stream_ptr, P, 4);
+                flags = bytestream2_get_le32(&s->stream_ptr);
             }
 
             for (x = 0; x < 4; x++, flags >>= 2)
@@ -441,20 +398,16 @@ static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
 
     } else {
         // vertical split?
-        int vert = s->stream_ptr[12] <= s->stream_ptr[13];
-        uint64_t flags = 0;
+        int vert;
+        uint64_t flags = bytestream2_get_le64(&s->stream_ptr);
+
+        bytestream2_get_buffer(&s->stream_ptr, P + 4, 4);
+        vert = P[4] <= P[5];
 
         /* 4-color encoding for either left and right or top and bottom
          * halves */
 
         for (y = 0; y < 16; y++) {
-            // load values for each half
-            if (!(y & 7)) {
-                memcpy(P, s->stream_ptr, 4);
-                s->stream_ptr += 4;
-                flags = bytestream_get_le64(&s->stream_ptr);
-            }
-
             for (x = 0; x < 4; x++, flags >>= 2)
                 *s->pixel_ptr++ = P[flags & 0x03];
 
@@ -463,6 +416,12 @@ static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
                 // switch to right half
                 if (y == 7) s->pixel_ptr -= 8 * s->stride - 4;
             } else if (y & 1) s->pixel_ptr += s->line_inc;
+
+            // load values for second half
+            if (y == 7) {
+                memcpy(P, P + 4, 4);
+                flags = bytestream2_get_le64(&s->stream_ptr);
+            }
         }
     }
 
@@ -475,11 +434,8 @@ static int ipvideo_decode_block_opcode_0xB(IpvideoContext *s)
     int y;
 
     /* 64-color encoding (each pixel in block is a different color) */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 64);
-
     for (y = 0; y < 8; y++) {
-        memcpy(s->pixel_ptr, s->stream_ptr, 8);
-        s->stream_ptr += 8;
+        bytestream2_get_buffer(&s->stream_ptr, s->pixel_ptr, 8);
         s->pixel_ptr  += s->stride;
     }
 
@@ -492,14 +448,12 @@ static int ipvideo_decode_block_opcode_0xC(IpvideoContext *s)
     int x, y;
 
     /* 16-color block encoding: each 2x2 block is a different color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
-
     for (y = 0; y < 8; y += 2) {
         for (x = 0; x < 8; x += 2) {
             s->pixel_ptr[x                ] =
             s->pixel_ptr[x + 1            ] =
             s->pixel_ptr[x +     s->stride] =
-            s->pixel_ptr[x + 1 + s->stride] = *s->stream_ptr++;
+            s->pixel_ptr[x + 1 + s->stride] = bytestream2_get_byte(&s->stream_ptr);
         }
         s->pixel_ptr += s->stride * 2;
     }
@@ -514,12 +468,10 @@ static int ipvideo_decode_block_opcode_0xD(IpvideoContext *s)
     unsigned char P[2];
 
     /* 4-color block encoding: each 4x4 block is a different color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
     for (y = 0; y < 8; y++) {
         if (!(y & 3)) {
-            P[0] = *s->stream_ptr++;
-            P[1] = *s->stream_ptr++;
+            P[0] = bytestream2_get_byte(&s->stream_ptr);
+            P[1] = bytestream2_get_byte(&s->stream_ptr);
         }
         memset(s->pixel_ptr,     P[0], 4);
         memset(s->pixel_ptr + 4, P[1], 4);
@@ -536,8 +488,7 @@ static int ipvideo_decode_block_opcode_0xE(IpvideoContext *s)
     unsigned char pix;
 
     /* 1-color encoding: the whole block is 1 solid color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
-    pix = *s->stream_ptr++;
+    pix = bytestream2_get_byte(&s->stream_ptr);
 
     for (y = 0; y < 8; y++) {
         memset(s->pixel_ptr, pix, 8);
@@ -554,9 +505,8 @@ static int ipvideo_decode_block_opcode_0xF(IpvideoContext *s)
     unsigned char sample[2];
 
     /* dithered encoding */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-    sample[0] = *s->stream_ptr++;
-    sample[1] = *s->stream_ptr++;
+    sample[0] = bytestream2_get_byte(&s->stream_ptr);
+    sample[1] = bytestream2_get_byte(&s->stream_ptr);
 
     for (y = 0; y < 8; y++) {
         for (x = 0; x < 8; x += 2) {
@@ -575,10 +525,8 @@ static int ipvideo_decode_block_opcode_0x6_16(IpvideoContext *s)
     signed char x, y;
 
     /* copy a block from the second last frame using an expanded range */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-    x = *s->stream_ptr++;
-    y = *s->stream_ptr++;
+    x = bytestream2_get_byte(&s->stream_ptr);
+    y = bytestream2_get_byte(&s->stream_ptr);
 
     av_dlog(NULL, "    motion bytes = %d, %d\n", x, y);
     return copy_from(s, &s->second_last_frame, x, y);
@@ -592,17 +540,13 @@ static int ipvideo_decode_block_opcode_0x7_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 2-color encoding */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
-    P[0] = bytestream_get_le16(&s->stream_ptr);
-    P[1] = bytestream_get_le16(&s->stream_ptr);
+    P[0] = bytestream2_get_le16(&s->stream_ptr);
+    P[1] = bytestream2_get_le16(&s->stream_ptr);
 
     if (!(P[0] & 0x8000)) {
 
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
         for (y = 0; y < 8; y++) {
-            flags = *s->stream_ptr++ | 0x100;
+            flags = bytestream2_get_byte(&s->stream_ptr) | 0x100;
             for (; flags != 1; flags >>= 1)
                 *pixel_ptr++ = P[flags & 1];
             pixel_ptr += s->line_inc;
@@ -610,9 +554,7 @@ static int ipvideo_decode_block_opcode_0x7_16(IpvideoContext *s)
 
     } else {
 
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-
-        flags = bytestream_get_le16(&s->stream_ptr);
+        flags = bytestream2_get_le16(&s->stream_ptr);
         for (y = 0; y < 8; y += 2) {
             for (x = 0; x < 8; x += 2, flags >>= 1) {
                 pixel_ptr[x                ] =
@@ -630,28 +572,25 @@ static int ipvideo_decode_block_opcode_0x7_16(IpvideoContext *s)
 static int ipvideo_decode_block_opcode_0x8_16(IpvideoContext *s)
 {
     int x, y;
-    uint16_t P[2];
+    uint16_t P[4];
     unsigned int flags = 0;
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
      * either top and bottom or left and right halves */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
-    P[0] = bytestream_get_le16(&s->stream_ptr);
-    P[1] = bytestream_get_le16(&s->stream_ptr);
+    P[0] = bytestream2_get_le16(&s->stream_ptr);
+    P[1] = bytestream2_get_le16(&s->stream_ptr);
 
     if (!(P[0] & 0x8000)) {
 
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
-        s->stream_ptr -= 4;
-
         for (y = 0; y < 16; y++) {
             // new values for each 4x4 block
             if (!(y & 3)) {
-                P[0] = bytestream_get_le16(&s->stream_ptr);
-                P[1] = bytestream_get_le16(&s->stream_ptr);
-                flags = bytestream_get_le16(&s->stream_ptr);
+                if (y) {
+                    P[0] = bytestream2_get_le16(&s->stream_ptr);
+                    P[1] = bytestream2_get_le16(&s->stream_ptr);
+                }
+                flags = bytestream2_get_le16(&s->stream_ptr);
             }
 
             for (x = 0; x < 4; x++, flags >>= 1)
@@ -663,11 +602,11 @@ static int ipvideo_decode_block_opcode_0x8_16(IpvideoContext *s)
 
     } else {
 
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 12);
-
-        if (!(AV_RL16(s->stream_ptr + 4) & 0x8000)) {
+        flags = bytestream2_get_le32(&s->stream_ptr);
+        P[2]  = bytestream2_get_le16(&s->stream_ptr);
+        P[3]  = bytestream2_get_le16(&s->stream_ptr);
 
-            flags = bytestream_get_le32(&s->stream_ptr);
+        if (!(P[2] & 0x8000)) {
 
             /* vertical split; left & right halves are 2-color encoded */
 
@@ -678,9 +617,9 @@ static int ipvideo_decode_block_opcode_0x8_16(IpvideoContext *s)
                 // switch to right half
                 if (y == 7) {
                     pixel_ptr -= 8 * s->stride - 4;
-                    P[0] = bytestream_get_le16(&s->stream_ptr);
-                    P[1] = bytestream_get_le16(&s->stream_ptr);
-                    flags = bytestream_get_le32(&s->stream_ptr);
+                    P[0]  = P[2];
+                    P[1]  = P[3];
+                    flags = bytestream2_get_le32(&s->stream_ptr);
                 }
             }
 
@@ -690,12 +629,12 @@ static int ipvideo_decode_block_opcode_0x8_16(IpvideoContext *s)
 
             for (y = 0; y < 8; y++) {
                 if (y == 4) {
-                    P[0] = bytestream_get_le16(&s->stream_ptr);
-                    P[1] = bytestream_get_le16(&s->stream_ptr);
+                    P[0]  = P[2];
+                    P[1]  = P[3];
+                    flags = bytestream2_get_le32(&s->stream_ptr);
                 }
-                flags = *s->stream_ptr++ | 0x100;
 
-                for (; flags != 1; flags >>= 1)
+                for (x = 0; x < 8; x++, flags >>= 1)
                     *pixel_ptr++ = P[flags & 1];
                 pixel_ptr += s->line_inc;
             }
@@ -713,20 +652,16 @@ static int ipvideo_decode_block_opcode_0x9_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 4-color encoding */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
     for (x = 0; x < 4; x++)
-        P[x] = bytestream_get_le16(&s->stream_ptr);
+        P[x] = bytestream2_get_le16(&s->stream_ptr);
 
     if (!(P[0] & 0x8000)) {
         if (!(P[2] & 0x8000)) {
 
             /* 1 of 4 colors for each pixel */
-            CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
-
             for (y = 0; y < 8; y++) {
                 /* get the next set of 8 2-bit flags */
-                int flags = bytestream_get_le16(&s->stream_ptr);
+                int flags = bytestream2_get_le16(&s->stream_ptr);
                 for (x = 0; x < 8; x++, flags >>= 2)
                     *pixel_ptr++ = P[flags & 0x03];
                 pixel_ptr += s->line_inc;
@@ -736,9 +671,7 @@ static int ipvideo_decode_block_opcode_0x9_16(IpvideoContext *s)
             uint32_t flags;
 
             /* 1 of 4 colors for each 2x2 block */
-            CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
-
-            flags = bytestream_get_le32(&s->stream_ptr);
+            flags = bytestream2_get_le32(&s->stream_ptr);
 
             for (y = 0; y < 8; y += 2) {
                 for (x = 0; x < 8; x += 2, flags >>= 2) {
@@ -755,9 +688,7 @@ static int ipvideo_decode_block_opcode_0x9_16(IpvideoContext *s)
         uint64_t flags;
 
         /* 1 of 4 colors for each 2x1 or 1x2 block */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
-        flags = bytestream_get_le64(&s->stream_ptr);
+        flags = bytestream2_get_le64(&s->stream_ptr);
         if (!(P[2] & 0x8000)) {
             for (y = 0; y < 8; y++) {
                 for (x = 0; x < 8; x += 2, flags >>= 2) {
@@ -784,25 +715,25 @@ static int ipvideo_decode_block_opcode_0x9_16(IpvideoContext *s)
 static int ipvideo_decode_block_opcode_0xA_16(IpvideoContext *s)
 {
     int x, y;
-    uint16_t P[4];
+    uint16_t P[8];
     int flags = 0;
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
+    for (x = 0; x < 4; x++)
+        P[x] = bytestream2_get_le16(&s->stream_ptr);
+
     /* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
      * either top and bottom or left and right halves */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
-
-    if (!(AV_RL16(s->stream_ptr) & 0x8000)) {
+    if (!(P[0] & 0x8000)) {
 
         /* 4-color encoding for each quadrant */
-        CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 48);
-
         for (y = 0; y < 16; y++) {
             // new values for each 4x4 block
             if (!(y & 3)) {
-                for (x = 0; x < 4; x++)
-                    P[x] = bytestream_get_le16(&s->stream_ptr);
-                flags = bytestream_get_le32(&s->stream_ptr);
+                if (y)
+                    for (x = 0; x < 4; x++)
+                        P[x] = bytestream2_get_le16(&s->stream_ptr);
+                flags = bytestream2_get_le32(&s->stream_ptr);
             }
 
             for (x = 0; x < 4; x++, flags >>= 2)
@@ -815,20 +746,17 @@ static int ipvideo_decode_block_opcode_0xA_16(IpvideoContext *s)
 
     } else {
         // vertical split?
-        int vert = !(AV_RL16(s->stream_ptr + 16) & 0x8000);
-        uint64_t flags = 0;
+        int vert;
+        uint64_t flags = bytestream2_get_le64(&s->stream_ptr);
+
+        for (x = 4; x < 8; x++)
+            P[x] = bytestream2_get_le16(&s->stream_ptr);
+        vert = !(P[4] & 0x8000);
 
         /* 4-color encoding for either left and right or top and bottom
          * halves */
 
         for (y = 0; y < 16; y++) {
-            // load values for each half
-            if (!(y & 7)) {
-                for (x = 0; x < 4; x++)
-                    P[x] = bytestream_get_le16(&s->stream_ptr);
-                flags = bytestream_get_le64(&s->stream_ptr);
-            }
-
             for (x = 0; x < 4; x++, flags >>= 2)
                 *pixel_ptr++ = P[flags & 0x03];
 
@@ -837,6 +765,12 @@ static int ipvideo_decode_block_opcode_0xA_16(IpvideoContext *s)
                 // switch to right half
                 if (y == 7) pixel_ptr -= 8 * s->stride - 4;
             } else if (y & 1) pixel_ptr += s->line_inc;
+
+            // load values for second half
+            if (y == 7) {
+                memcpy(P, P + 4, 8);
+                flags = bytestream2_get_le64(&s->stream_ptr);
+            }
         }
     }
 
@@ -850,11 +784,9 @@ static int ipvideo_decode_block_opcode_0xB_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 64-color encoding (each pixel in block is a different color) */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 128);
-
     for (y = 0; y < 8; y++) {
         for (x = 0; x < 8; x++)
-            pixel_ptr[x] = bytestream_get_le16(&s->stream_ptr);
+            pixel_ptr[x] = bytestream2_get_le16(&s->stream_ptr);
         pixel_ptr  += s->stride;
     }
 
@@ -868,14 +800,12 @@ static int ipvideo_decode_block_opcode_0xC_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 16-color block encoding: each 2x2 block is a different color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 32);
-
     for (y = 0; y < 8; y += 2) {
         for (x = 0; x < 8; x += 2) {
             pixel_ptr[x                ] =
             pixel_ptr[x + 1            ] =
             pixel_ptr[x +     s->stride] =
-            pixel_ptr[x + 1 + s->stride] = bytestream_get_le16(&s->stream_ptr);
+            pixel_ptr[x + 1 + s->stride] = bytestream2_get_le16(&s->stream_ptr);
         }
         pixel_ptr += s->stride * 2;
     }
@@ -891,12 +821,10 @@ static int ipvideo_decode_block_opcode_0xD_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 4-color block encoding: each 4x4 block is a different color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
-
     for (y = 0; y < 8; y++) {
         if (!(y & 3)) {
-            P[0] = bytestream_get_le16(&s->stream_ptr);
-            P[1] = bytestream_get_le16(&s->stream_ptr);
+            P[0] = bytestream2_get_le16(&s->stream_ptr);
+            P[1] = bytestream2_get_le16(&s->stream_ptr);
         }
         for (x = 0; x < 8; x++)
             pixel_ptr[x] = P[x >> 2];
@@ -914,8 +842,7 @@ static int ipvideo_decode_block_opcode_0xE_16(IpvideoContext *s)
     uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
 
     /* 1-color encoding: the whole block is 1 solid color */
-    CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
-    pix = bytestream_get_le16(&s->stream_ptr);
+    pix = bytestream2_get_le16(&s->stream_ptr);
 
     for (y = 0; y < 8; y++) {
         for (x = 0; x < 8; x++)
@@ -960,19 +887,16 @@ static void ipvideo_decode_opcodes(IpvideoContext *s)
     av_dlog(NULL, "------------------ frame %d\n", frame);
     frame++;
 
+    bytestream2_skip(&s->stream_ptr, 14); /* data starts 14 bytes in */
     if (!s->is_16bpp) {
         /* this is PAL8, so make the palette available */
         memcpy(s->current_frame.data[1], s->pal, AVPALETTE_SIZE);
 
         s->stride = s->current_frame.linesize[0];
-        s->stream_ptr = s->buf + 14;  /* data starts 14 bytes in */
-        s->stream_end = s->buf + s->size;
     } else {
         s->stride = s->current_frame.linesize[0] >> 1;
-        s->stream_ptr = s->buf + 16;
-        s->stream_end =
-        s->mv_ptr = s->buf + 14 + AV_RL16(s->buf+14);
-        s->mv_end = s->buf + s->size;
+        s->mv_ptr = s->stream_ptr;
+        bytestream2_skip(&s->mv_ptr, bytestream2_get_le16(&s->stream_ptr));
     }
     s->line_inc = s->stride - 8;
     s->upper_motion_limit_offset = (s->avctx->height - 8) * s->current_frame.linesize[0]
@@ -1002,9 +926,10 @@ static void ipvideo_decode_opcodes(IpvideoContext *s)
             }
         }
     }
-    if (s->stream_end - s->stream_ptr > 1) {
-        av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode finished with %td bytes left over\n",
-               s->stream_end - s->stream_ptr);
+    if (bytestream2_get_bytes_left(&s->stream_ptr) > 1) {
+        av_log(s->avctx, AV_LOG_ERROR,
+               "Interplay video: decode finished with %d bytes left over\n",
+               bytestream2_get_bytes_left(&s->stream_ptr));
     }
 }
 
@@ -1042,8 +967,8 @@ static int ipvideo_decode_frame(AVCodecContext *avctx,
         return buf_size;
 
     s->decoding_map = buf;
-    s->buf = buf + s->decoding_map_size;
-    s->size = buf_size - s->decoding_map_size;
+    bytestream2_init(&s->stream_ptr, buf + s->decoding_map_size,
+                     buf_size - s->decoding_map_size);
 
     s->current_frame.reference = 3;
     if (avctx->get_buffer(avctx, &s->current_frame)) {