@@ -273,6 +273,73 @@ static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_siz

     }

 }

+static int read_header(ShortenContext *s)

+{

+    int i;

+    int maxnlpc = 0;

+    /* shorten signature */

+    if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {

+        av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");

+        return -1;

+    }

+

+    s->lpcqoffset = 0;

+    s->blocksize = DEFAULT_BLOCK_SIZE;

+    s->channels = 1;

+    s->nmean = -1;

+    s->version = get_bits(&s->gb, 8);

+    s->internal_ftype = get_uint(s, TYPESIZE);

+

+    s->channels = get_uint(s, CHANSIZE);

+    if (s->channels > MAX_CHANNELS) {

+        av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);

+        return -1;

+    }

+

+    /* get blocksize if version > 0 */

+    if (s->version > 0) {

+        int skip_bytes;

+        s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));

+        maxnlpc = get_uint(s, LPCQSIZE);

+        s->nmean = get_uint(s, 0);

+

+        skip_bytes = get_uint(s, NSKIPSIZE);

+        for (i=0; i<skip_bytes; i++) {

+            skip_bits(&s->gb, 8);

+        }

+    }

+    s->nwrap = FFMAX(NWRAP, maxnlpc);

+

+    if (allocate_buffers(s))

+        return -1;

+

+    init_offset(s);

+

+    if (s->version > 1)

+        s->lpcqoffset = V2LPCQOFFSET;

+

+    if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {

+        av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");

+        return -1;

+    }

+

+    s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);

+    if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {

+        av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);

+        return -1;

+    }

+

+    for (i=0; i<s->header_size; i++)

+        s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);

+

+    if (decode_wave_header(s->avctx, s->header, s->header_size) < 0)

+        return -1;

+

+    s->cur_chan = 0;

+    s->bitshift = 0;

+

+    return 0;

+}

 static int shorten_decode_frame(AVCodecContext *avctx,

         void *data, int *data_size,

@@ -311,67 +378,9 @@ static int shorten_decode_frame(AVCodecContext *avctx,

     skip_bits(&s->gb, s->bitindex);

     if (!s->blocksize)

     {

-        int maxnlpc = 0;

-        /* shorten signature */

-        if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {

-            av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");

-            return -1;

-        }

-

-        s->lpcqoffset = 0;

-        s->blocksize = DEFAULT_BLOCK_SIZE;

-        s->channels = 1;

-        s->nmean = -1;

-        s->version = get_bits(&s->gb, 8);

-        s->internal_ftype = get_uint(s, TYPESIZE);

-

-        s->channels = get_uint(s, CHANSIZE);

-        if (s->channels > MAX_CHANNELS) {

-            av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);

-            return -1;

-        }

-

-        /* get blocksize if version > 0 */

-        if (s->version > 0) {

-            int skip_bytes;

-            s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));

-            maxnlpc = get_uint(s, LPCQSIZE);

-            s->nmean = get_uint(s, 0);

-

-            skip_bytes = get_uint(s, NSKIPSIZE);

-            for (i=0; i<skip_bytes; i++) {

-                skip_bits(&s->gb, 8);

-            }

-        }

-        s->nwrap = FFMAX(NWRAP, maxnlpc);

-

-        if (allocate_buffers(s))

-            return -1;

-

-        init_offset(s);

-

-        if (s->version > 1)

-            s->lpcqoffset = V2LPCQOFFSET;

-

-        if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {

-            av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");

-            return -1;

-        }

-

-        s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);

-        if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {

-            av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);

-            return -1;

-        }

-

-        for (i=0; i<s->header_size; i++)

-            s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);

-

-        if (decode_wave_header(avctx, s->header, s->header_size) < 0)

-            return -1;

-

-        s->cur_chan = 0;

-        s->bitshift = 0;

+        int ret;

+        if ((ret = read_header(s)) < 0)

+            return ret;

     }

     else

     {