]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/flicvideo.c
dv: Initialize encoder tables during encoder init.
[ffmpeg] / libavcodec / flicvideo.c
index 4a8cb5e043542d4a181a885a0d2d0d474e47817a..d6c4934e88ced43d9289c877a50a3de459d761a6 100644 (file)
@@ -2,25 +2,25 @@
  * FLI/FLC Animation Video Decoder
  * Copyright (C) 2003, 2004 the ffmpeg project
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**
- * @file flic.c
+ * @file
  * Autodesk Animator FLI/FLC Video Decoder
  * by Mike Melanson (melanson@pcisys.net)
  * for more information on the .fli/.flc file format and all of its many
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
-#include "libavutil/bswap.h"
+#include "libavutil/intreadwrite.h"
 #include "avcodec.h"
+#include "bytestream.h"
+#include "mathops.h"
 
 #define FLI_256_COLOR 4
 #define FLI_DELTA     7
@@ -82,6 +83,12 @@ static av_cold int flic_decode_init(AVCodecContext *avctx)
     unsigned char *fli_header = (unsigned char *)avctx->extradata;
     int depth;
 
+    if (avctx->extradata_size != 12 &&
+        avctx->extradata_size != 128) {
+        av_log(avctx, AV_LOG_ERROR, "Expected extradata of 12 or 128 bytes\n");
+        return AVERROR_INVALIDDATA;
+    }
+
     s->avctx = avctx;
 
     s->fli_type = AV_RL16(&fli_header[4]); /* Might be overridden if a Magic Carpet FLC */
@@ -91,9 +98,6 @@ static av_cold int flic_decode_init(AVCodecContext *avctx)
         /* special case for magic carpet FLIs */
         s->fli_type = FLC_MAGIC_CARPET_SYNTHETIC_TYPE_CODE;
         depth = 8;
-    } else if (s->avctx->extradata_size != 128) {
-        av_log(avctx, AV_LOG_ERROR, "Expected extradata of 12 or 128 bytes\n");
-        return -1;
     } else {
         depth = AV_RL16(&fli_header[12]);
     }
@@ -113,7 +117,6 @@ static av_cold int flic_decode_init(AVCodecContext *avctx)
         case 24 : avctx->pix_fmt = PIX_FMT_BGR24; /* Supposedly BGR, but havent any files to test with */
                   av_log(avctx, AV_LOG_ERROR, "24Bpp FLC/FLX is unsupported due to no test files.\n");
                   return -1;
-                  break;
         default :
                   av_log(avctx, AV_LOG_ERROR, "Unknown FLC/FLX depth of %d Bpp is unsupported.\n",depth);
                   return -1;
@@ -131,7 +134,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
 {
     FlicDecodeContext *s = avctx->priv_data;
 
-    int stream_ptr = 0;
+    GetByteContext g2;
     int stream_ptr_after_color_chunk;
     int pixel_ptr;
     int palette_ptr;
@@ -160,7 +163,9 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
     int pixel_skip;
     int pixel_countdown;
     unsigned char *pixels;
-    int pixel_limit;
+    unsigned int pixel_limit;
+
+    bytestream2_init(&g2, buf, buf_size);
 
     s->frame.reference = 1;
     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
@@ -171,25 +176,22 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
 
     pixels = s->frame.data[0];
     pixel_limit = s->avctx->height * s->frame.linesize[0];
-
-    frame_size = AV_RL32(&buf[stream_ptr]);
-    stream_ptr += 6;  /* skip the magic number */
-    num_chunks = AV_RL16(&buf[stream_ptr]);
-    stream_ptr += 10;  /* skip padding */
+    frame_size = bytestream2_get_le32(&g2);
+    bytestream2_skip(&g2, 2); /* skip the magic number */
+    num_chunks = bytestream2_get_le16(&g2);
+    bytestream2_skip(&g2, 8);  /* skip padding */
 
     frame_size -= 16;
 
     /* iterate through the chunks */
     while ((frame_size > 0) && (num_chunks > 0)) {
-        chunk_size = AV_RL32(&buf[stream_ptr]);
-        stream_ptr += 4;
-        chunk_type = AV_RL16(&buf[stream_ptr]);
-        stream_ptr += 2;
+        chunk_size = bytestream2_get_le32(&g2);
+        chunk_type = bytestream2_get_le16(&g2);
 
         switch (chunk_type) {
         case FLI_256_COLOR:
         case FLI_COLOR:
-            stream_ptr_after_color_chunk = stream_ptr + chunk_size - 6;
+            stream_ptr_after_color_chunk = bytestream2_tell(&g2) + chunk_size - 6;
 
             /* check special case: If this file is from the Magic Carpet
              * game and uses 6-bit colors even though it reports 256-color
@@ -200,15 +202,14 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
             else
                 color_shift = 2;
             /* set up the palette */
-            color_packets = AV_RL16(&buf[stream_ptr]);
-            stream_ptr += 2;
+            color_packets = bytestream2_get_le16(&g2);
             palette_ptr = 0;
             for (i = 0; i < color_packets; i++) {
                 /* first byte is how many colors to skip */
-                palette_ptr += buf[stream_ptr++];
+                palette_ptr += bytestream2_get_byte(&g2);
 
                 /* next byte indicates how many entries to change */
-                color_changes = buf[stream_ptr++];
+                color_changes = bytestream2_get_byte(&g2);
 
                 /* if there are 0 color changes, there are actually 256 */
                 if (color_changes == 0)
@@ -221,9 +222,9 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                     if ((unsigned)palette_ptr >= 256)
                         palette_ptr = 0;
 
-                    r = buf[stream_ptr++] << color_shift;
-                    g = buf[stream_ptr++] << color_shift;
-                    b = buf[stream_ptr++] << color_shift;
+                    r = bytestream2_get_byte(&g2) << color_shift;
+                    g = bytestream2_get_byte(&g2) << color_shift;
+                    b = bytestream2_get_byte(&g2) << color_shift;
                     entry = (r << 16) | (g << 8) | b;
                     if (s->palette[palette_ptr] != entry)
                         s->new_palette = 1;
@@ -232,20 +233,19 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
             }
 
             /* color chunks sometimes have weird 16-bit alignment issues;
-             * therefore, take the hardline approach and set the stream_ptr
+             * therefore, take the hardline approach and skip
              * to the value calculated w.r.t. the size specified by the color
              * chunk header */
-            stream_ptr = stream_ptr_after_color_chunk;
+            if (stream_ptr_after_color_chunk - bytestream2_tell(&g2) > 0)
+                bytestream2_skip(&g2, stream_ptr_after_color_chunk - bytestream2_tell(&g2));
 
             break;
 
         case FLI_DELTA:
             y_ptr = 0;
-            compressed_lines = AV_RL16(&buf[stream_ptr]);
-            stream_ptr += 2;
+            compressed_lines = bytestream2_get_le16(&g2);
             while (compressed_lines > 0) {
-                line_packets = AV_RL16(&buf[stream_ptr]);
-                stream_ptr += 2;
+                line_packets = bytestream2_get_le16(&g2);
                 if ((line_packets & 0xC000) == 0xC000) {
                     // line skip opcode
                     line_packets = -line_packets;
@@ -254,22 +254,25 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                     av_log(avctx, AV_LOG_ERROR, "Undefined opcode (%x) in DELTA_FLI\n", line_packets);
                 } else if ((line_packets & 0xC000) == 0x8000) {
                     // "last byte" opcode
-                    pixels[y_ptr + s->frame.linesize[0] - 1] = line_packets & 0xff;
+                    pixel_ptr= y_ptr + s->frame.linesize[0] - 1;
+                    CHECK_PIXEL_PTR(0);
+                    pixels[pixel_ptr] = line_packets & 0xff;
                 } else {
                     compressed_lines--;
                     pixel_ptr = y_ptr;
+                    CHECK_PIXEL_PTR(0);
                     pixel_countdown = s->avctx->width;
                     for (i = 0; i < line_packets; i++) {
                         /* account for the skip bytes */
-                        pixel_skip = buf[stream_ptr++];
+                        pixel_skip = bytestream2_get_byte(&g2);
                         pixel_ptr += pixel_skip;
                         pixel_countdown -= pixel_skip;
-                        byte_run = (signed char)(buf[stream_ptr++]);
+                        byte_run = sign_extend(bytestream2_get_byte(&g2), 8);
                         if (byte_run < 0) {
                             byte_run = -byte_run;
-                            palette_idx1 = buf[stream_ptr++];
-                            palette_idx2 = buf[stream_ptr++];
-                            CHECK_PIXEL_PTR(byte_run);
+                            palette_idx1 = bytestream2_get_byte(&g2);
+                            palette_idx2 = bytestream2_get_byte(&g2);
+                            CHECK_PIXEL_PTR(byte_run * 2);
                             for (j = 0; j < byte_run; j++, pixel_countdown -= 2) {
                                 pixels[pixel_ptr++] = palette_idx1;
                                 pixels[pixel_ptr++] = palette_idx2;
@@ -277,8 +280,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                         } else {
                             CHECK_PIXEL_PTR(byte_run * 2);
                             for (j = 0; j < byte_run * 2; j++, pixel_countdown--) {
-                                palette_idx1 = buf[stream_ptr++];
-                                pixels[pixel_ptr++] = palette_idx1;
+                                pixels[pixel_ptr++] = bytestream2_get_byte(&g2);
                             }
                         }
                     }
@@ -290,33 +292,31 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
 
         case FLI_LC:
             /* line compressed */
-            starting_line = AV_RL16(&buf[stream_ptr]);
-            stream_ptr += 2;
+            starting_line = bytestream2_get_le16(&g2);
             y_ptr = 0;
             y_ptr += starting_line * s->frame.linesize[0];
 
-            compressed_lines = AV_RL16(&buf[stream_ptr]);
-            stream_ptr += 2;
+            compressed_lines = bytestream2_get_le16(&g2);
             while (compressed_lines > 0) {
                 pixel_ptr = y_ptr;
+                CHECK_PIXEL_PTR(0);
                 pixel_countdown = s->avctx->width;
-                line_packets = buf[stream_ptr++];
+                line_packets = bytestream2_get_byte(&g2);
                 if (line_packets > 0) {
                     for (i = 0; i < line_packets; i++) {
                         /* account for the skip bytes */
-                        pixel_skip = buf[stream_ptr++];
+                        pixel_skip = bytestream2_get_byte(&g2);
                         pixel_ptr += pixel_skip;
                         pixel_countdown -= pixel_skip;
-                        byte_run = (signed char)(buf[stream_ptr++]);
+                        byte_run = sign_extend(bytestream2_get_byte(&g2),8);
                         if (byte_run > 0) {
                             CHECK_PIXEL_PTR(byte_run);
                             for (j = 0; j < byte_run; j++, pixel_countdown--) {
-                                palette_idx1 = buf[stream_ptr++];
-                                pixels[pixel_ptr++] = palette_idx1;
+                                pixels[pixel_ptr++] = bytestream2_get_byte(&g2);
                             }
                         } else if (byte_run < 0) {
                             byte_run = -byte_run;
-                            palette_idx1 = buf[stream_ptr++];
+                            palette_idx1 = bytestream2_get_byte(&g2);
                             CHECK_PIXEL_PTR(byte_run);
                             for (j = 0; j < byte_run; j++, pixel_countdown--) {
                                 pixels[pixel_ptr++] = palette_idx1;
@@ -344,12 +344,12 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                 pixel_ptr = y_ptr;
                 /* disregard the line packets; instead, iterate through all
                  * pixels on a row */
-                stream_ptr++;
+                 bytestream2_skip(&g2, 1);
                 pixel_countdown = s->avctx->width;
                 while (pixel_countdown > 0) {
-                    byte_run = (signed char)(buf[stream_ptr++]);
+                    byte_run = sign_extend(bytestream2_get_byte(&g2), 8);
                     if (byte_run > 0) {
-                        palette_idx1 = buf[stream_ptr++];
+                        palette_idx1 = bytestream2_get_byte(&g2);
                         CHECK_PIXEL_PTR(byte_run);
                         for (j = 0; j < byte_run; j++) {
                             pixels[pixel_ptr++] = palette_idx1;
@@ -362,8 +362,7 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
                         byte_run = -byte_run;
                         CHECK_PIXEL_PTR(byte_run);
                         for (j = 0; j < byte_run; j++) {
-                            palette_idx1 = buf[stream_ptr++];
-                            pixels[pixel_ptr++] = palette_idx1;
+                            pixels[pixel_ptr++] = bytestream2_get_byte(&g2);
                             pixel_countdown--;
                             if (pixel_countdown < 0)
                                 av_log(avctx, AV_LOG_ERROR, "pixel_countdown < 0 (%d) at line %d\n",
@@ -381,20 +380,19 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
             if (chunk_size - 6 > s->avctx->width * s->avctx->height) {
                 av_log(avctx, AV_LOG_ERROR, "In chunk FLI_COPY : source data (%d bytes) " \
                        "bigger than image, skipping chunk\n", chunk_size - 6);
-                stream_ptr += chunk_size - 6;
+                bytestream2_skip(&g2, chunk_size - 6);
             } else {
                 for (y_ptr = 0; y_ptr < s->frame.linesize[0] * s->avctx->height;
                      y_ptr += s->frame.linesize[0]) {
-                    memcpy(&pixels[y_ptr], &buf[stream_ptr],
-                        s->avctx->width);
-                    stream_ptr += s->avctx->width;
+                    bytestream2_get_buffer(&g2, &pixels[y_ptr],
+                                           s->avctx->width);
                 }
             }
             break;
 
         case FLI_MINI:
             /* some sort of a thumbnail? disregard this chunk... */
-            stream_ptr += chunk_size - 6;
+            bytestream2_skip(&g2, chunk_size - 6);
             break;
 
         default:
@@ -408,9 +406,11 @@ static int flic_decode_frame_8BPP(AVCodecContext *avctx,
 
     /* by the end of the chunk, the stream ptr should equal the frame
      * size (minus 1, possibly); if it doesn't, issue a warning */
-    if ((stream_ptr != buf_size) && (stream_ptr != buf_size - 1))
+    if ((bytestream2_get_bytes_left(&g2) != 0) &&
+        (bytestream2_get_bytes_left(&g2) != 1))
         av_log(avctx, AV_LOG_ERROR, "Processed FLI chunk where chunk size = %d " \
-               "and final chunk ptr = %d\n", buf_size, stream_ptr);
+               "and final chunk ptr = %d\n", buf_size,
+               buf_size - bytestream2_get_bytes_left(&g2));
 
     /* make the palette available on the way out */
     memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
@@ -433,7 +433,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
     /* Format is the pixel format, the packets are processed the same. */
     FlicDecodeContext *s = avctx->priv_data;
 
-    int stream_ptr = 0;
+    GetByteContext g2;
     int pixel_ptr;
     unsigned char palette_idx1;
 
@@ -454,7 +454,9 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
     int pixel_countdown;
     unsigned char *pixels;
     int pixel;
-    int pixel_limit;
+    unsigned int pixel_limit;
+
+    bytestream2_init(&g2, buf, buf_size);
 
     s->frame.reference = 1;
     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
@@ -466,19 +468,17 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
     pixels = s->frame.data[0];
     pixel_limit = s->avctx->height * s->frame.linesize[0];
 
-    frame_size = AV_RL32(&buf[stream_ptr]);
-    stream_ptr += 6;  /* skip the magic number */
-    num_chunks = AV_RL16(&buf[stream_ptr]);
-    stream_ptr += 10;  /* skip padding */
+    frame_size = bytestream2_get_le32(&g2);
+    bytestream2_skip(&g2, 2);  /* skip the magic number */
+    num_chunks = bytestream2_get_le16(&g2);
+    bytestream2_skip(&g2, 8);  /* skip padding */
 
     frame_size -= 16;
 
     /* iterate through the chunks */
     while ((frame_size > 0) && (num_chunks > 0)) {
-        chunk_size = AV_RL32(&buf[stream_ptr]);
-        stream_ptr += 4;
-        chunk_type = AV_RL16(&buf[stream_ptr]);
-        stream_ptr += 2;
+        chunk_size = bytestream2_get_le32(&g2);
+        chunk_type = bytestream2_get_le16(&g2);
 
         switch (chunk_type) {
         case FLI_256_COLOR:
@@ -487,44 +487,41 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
              * include one of these chunks in their first frame.
              * Why I do not know, it seems rather extraneous. */
 /*            av_log(avctx, AV_LOG_ERROR, "Unexpected Palette chunk %d in non-paletised FLC\n",chunk_type);*/
-            stream_ptr = stream_ptr + chunk_size - 6;
+            bytestream2_skip(&g2, chunk_size - 6);
             break;
 
         case FLI_DELTA:
         case FLI_DTA_LC:
             y_ptr = 0;
-            compressed_lines = AV_RL16(&buf[stream_ptr]);
-            stream_ptr += 2;
+            compressed_lines = bytestream2_get_le16(&g2);
             while (compressed_lines > 0) {
-                line_packets = AV_RL16(&buf[stream_ptr]);
-                stream_ptr += 2;
+                line_packets = bytestream2_get_le16(&g2);
                 if (line_packets < 0) {
                     line_packets = -line_packets;
                     y_ptr += line_packets * s->frame.linesize[0];
                 } else {
                     compressed_lines--;
                     pixel_ptr = y_ptr;
+                    CHECK_PIXEL_PTR(0);
                     pixel_countdown = s->avctx->width;
                     for (i = 0; i < line_packets; i++) {
                         /* account for the skip bytes */
-                        pixel_skip = buf[stream_ptr++];
+                        pixel_skip = bytestream2_get_byte(&g2);
                         pixel_ptr += (pixel_skip*2); /* Pixel is 2 bytes wide */
                         pixel_countdown -= pixel_skip;
-                        byte_run = (signed char)(buf[stream_ptr++]);
+                        byte_run = sign_extend(bytestream2_get_byte(&g2), 8);
                         if (byte_run < 0) {
                             byte_run = -byte_run;
-                            pixel    = AV_RL16(&buf[stream_ptr]);
-                            stream_ptr += 2;
-                            CHECK_PIXEL_PTR(byte_run);
+                            pixel    = bytestream2_get_le16(&g2);
+                            CHECK_PIXEL_PTR(2 * byte_run);
                             for (j = 0; j < byte_run; j++, pixel_countdown -= 2) {
                                 *((signed short*)(&pixels[pixel_ptr])) = pixel;
                                 pixel_ptr += 2;
                             }
                         } else {
-                            CHECK_PIXEL_PTR(byte_run);
+                            CHECK_PIXEL_PTR(2 * byte_run);
                             for (j = 0; j < byte_run; j++, pixel_countdown--) {
-                                *((signed short*)(&pixels[pixel_ptr])) = AV_RL16(&buf[stream_ptr]);
-                                stream_ptr += 2;
+                                *((signed short*)(&pixels[pixel_ptr])) = bytestream2_get_le16(&g2);
                                 pixel_ptr += 2;
                             }
                         }
@@ -537,7 +534,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
 
         case FLI_LC:
             av_log(avctx, AV_LOG_ERROR, "Unexpected FLI_LC chunk in non-paletised FLC\n");
-            stream_ptr = stream_ptr + chunk_size - 6;
+            bytestream2_skip(&g2, chunk_size - 6);
             break;
 
         case FLI_BLACK:
@@ -552,13 +549,13 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                 pixel_ptr = y_ptr;
                 /* disregard the line packets; instead, iterate through all
                  * pixels on a row */
-                stream_ptr++;
+                bytestream2_skip(&g2, 1);
                 pixel_countdown = (s->avctx->width * 2);
 
                 while (pixel_countdown > 0) {
-                    byte_run = (signed char)(buf[stream_ptr++]);
+                    byte_run = sign_extend(bytestream2_get_byte(&g2), 8);
                     if (byte_run > 0) {
-                        palette_idx1 = buf[stream_ptr++];
+                        palette_idx1 = bytestream2_get_byte(&g2);
                         CHECK_PIXEL_PTR(byte_run);
                         for (j = 0; j < byte_run; j++) {
                             pixels[pixel_ptr++] = palette_idx1;
@@ -571,7 +568,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                         byte_run = -byte_run;
                         CHECK_PIXEL_PTR(byte_run);
                         for (j = 0; j < byte_run; j++) {
-                            palette_idx1 = buf[stream_ptr++];
+                            palette_idx1 = bytestream2_get_byte(&g2);
                             pixels[pixel_ptr++] = palette_idx1;
                             pixel_countdown--;
                             if (pixel_countdown < 0)
@@ -586,7 +583,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                  * during decompression. So if it is required (i.e., this is not a LE target, we do
                  * a second pass over the line here, swapping the bytes.
                  */
-#ifdef WORDS_BIGENDIAN
+#if HAVE_BIGENDIAN
                 pixel_ptr = y_ptr;
                 pixel_countdown = s->avctx->width;
                 while (pixel_countdown > 0) {
@@ -604,15 +601,14 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                 pixel_ptr = y_ptr;
                 /* disregard the line packets; instead, iterate through all
                  * pixels on a row */
-                stream_ptr++;
+                bytestream2_skip(&g2, 1);
                 pixel_countdown = s->avctx->width; /* Width is in pixels, not bytes */
 
                 while (pixel_countdown > 0) {
-                    byte_run = (signed char)(buf[stream_ptr++]);
+                    byte_run = sign_extend(bytestream2_get_byte(&g2), 8);
                     if (byte_run > 0) {
-                        pixel    = AV_RL16(&buf[stream_ptr]);
-                        stream_ptr += 2;
-                        CHECK_PIXEL_PTR(byte_run);
+                        pixel    = bytestream2_get_le16(&g2);
+                        CHECK_PIXEL_PTR(2 * byte_run);
                         for (j = 0; j < byte_run; j++) {
                             *((signed short*)(&pixels[pixel_ptr])) = pixel;
                             pixel_ptr += 2;
@@ -623,10 +619,9 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                         }
                     } else {  /* copy pixels if byte_run < 0 */
                         byte_run = -byte_run;
-                        CHECK_PIXEL_PTR(byte_run);
+                        CHECK_PIXEL_PTR(2 * byte_run);
                         for (j = 0; j < byte_run; j++) {
-                            *((signed short*)(&pixels[pixel_ptr])) = AV_RL16(&buf[stream_ptr]);
-                            stream_ptr += 2;
+                            *((signed short*)(&pixels[pixel_ptr])) = bytestream2_get_le16(&g2);
                             pixel_ptr  += 2;
                             pixel_countdown--;
                             if (pixel_countdown < 0)
@@ -646,7 +641,7 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
             if (chunk_size - 6 > (unsigned int)(s->avctx->width * s->avctx->height)*2) {
                 av_log(avctx, AV_LOG_ERROR, "In chunk FLI_COPY : source data (%d bytes) " \
                        "bigger than image, skipping chunk\n", chunk_size - 6);
-                stream_ptr += chunk_size - 6;
+                bytestream2_skip(&g2, chunk_size - 6);
             } else {
 
                 for (y_ptr = 0; y_ptr < s->frame.linesize[0] * s->avctx->height;
@@ -655,18 +650,17 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
                     pixel_countdown = s->avctx->width;
                     pixel_ptr = 0;
                     while (pixel_countdown > 0) {
-                      *((signed short*)(&pixels[y_ptr + pixel_ptr])) = AV_RL16(&buf[stream_ptr+pixel_ptr]);
+                      *((signed short*)(&pixels[y_ptr + pixel_ptr])) = bytestream2_get_le16(&g2);
                       pixel_ptr += 2;
                       pixel_countdown--;
                     }
-                    stream_ptr += s->avctx->width*2;
                 }
             }
             break;
 
         case FLI_MINI:
             /* some sort of a thumbnail? disregard this chunk... */
-            stream_ptr += chunk_size - 6;
+            bytestream2_skip(&g2, chunk_size - 6);
             break;
 
         default:
@@ -680,9 +674,9 @@ static int flic_decode_frame_15_16BPP(AVCodecContext *avctx,
 
     /* by the end of the chunk, the stream ptr should equal the frame
      * size (minus 1, possibly); if it doesn't, issue a warning */
-    if ((stream_ptr != buf_size) && (stream_ptr != buf_size - 1))
+    if ((bytestream2_get_bytes_left(&g2) != 0) && (bytestream2_get_bytes_left(&g2) != 1))
         av_log(avctx, AV_LOG_ERROR, "Processed FLI chunk where chunk size = %d " \
-               "and final chunk ptr = %d\n", buf_size, stream_ptr);
+               "and final chunk ptr = %d\n", buf_size, bytestream2_tell(&g2));
 
 
     *data_size=sizeof(AVFrame);
@@ -701,8 +695,10 @@ static int flic_decode_frame_24BPP(AVCodecContext *avctx,
 
 static int flic_decode_frame(AVCodecContext *avctx,
                              void *data, int *data_size,
-                             const uint8_t *buf, int buf_size)
+                             AVPacket *avpkt)
 {
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
     if (avctx->pix_fmt == PIX_FMT_PAL8) {
       return flic_decode_frame_8BPP(avctx, data, data_size,
                                     buf, buf_size);
@@ -736,19 +732,14 @@ static av_cold int flic_decode_end(AVCodecContext *avctx)
     return 0;
 }
 
-AVCodec flic_decoder = {
-    "flic",
-    CODEC_TYPE_VIDEO,
-    CODEC_ID_FLIC,
-    sizeof(FlicDecodeContext),
-    flic_decode_init,
-    NULL,
-    flic_decode_end,
-    flic_decode_frame,
-    CODEC_CAP_DR1,
-    NULL,
-    NULL,
-    NULL,
-    NULL,
-    .long_name = NULL_IF_CONFIG_SMALL("Autodesk Animator Flic video"),
+AVCodec ff_flic_decoder = {
+    .name           = "flic",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = CODEC_ID_FLIC,
+    .priv_data_size = sizeof(FlicDecodeContext),
+    .init           = flic_decode_init,
+    .close          = flic_decode_end,
+    .decode         = flic_decode_frame,
+    .capabilities   = CODEC_CAP_DR1,
+    .long_name      = NULL_IF_CONFIG_SMALL("Autodesk Animator Flic video"),
 };