Decode the codec private data and following ContentEncoding if necessary.

Original commit message from CVS:
* configure.ac:
* gst/matroska/Makefile.am:
* gst/matroska/lzo.c: (get_byte), (get_len), (copy),
(copy_backptr), (lzo1x_decode), (main):
* gst/matroska/lzo.h:
* gst/matroska/matroska-demux.c:
(gst_matroska_demux_read_track_encoding),
(gst_matroska_decompress_data), (gst_matroska_decode_data),
(gst_matroska_decode_buffer),
(gst_matroska_decode_content_encodings),
(gst_matroska_demux_read_track_encodings),
(gst_matroska_demux_add_stream),
(gst_matroska_demux_parse_blockgroup_or_simpleblock):
* gst/matroska/matroska-ids.h:
Decode the codec private data and following ContentEncoding if
necessary.
Support bzip2, lzo and header stripped compression. For lzo use the
ffmpeg lzo implementation as liblzo is GPL licensed.
Fix zlib decompression.

7 files changed, 719 insertions, 112 deletions

diff --git a/ChangeLog b/ChangeLog
index 3c955cb3..03a65383 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,29 @@
 2008-08-02  Sebastian Dröge  <sebastian.droege@collabora.co.uk>
 
+	* configure.ac:
+	* gst/matroska/Makefile.am:
+	* gst/matroska/lzo.c: (get_byte), (get_len), (copy),
+	(copy_backptr), (lzo1x_decode), (main):
+	* gst/matroska/lzo.h:
+	* gst/matroska/matroska-demux.c:
+	(gst_matroska_demux_read_track_encoding),
+	(gst_matroska_decompress_data), (gst_matroska_decode_data),
+	(gst_matroska_decode_buffer),
+	(gst_matroska_decode_content_encodings),
+	(gst_matroska_demux_read_track_encodings),
+	(gst_matroska_demux_add_stream),
+	(gst_matroska_demux_parse_blockgroup_or_simpleblock):
+	* gst/matroska/matroska-ids.h:
+	Decode the codec private data and following ContentEncoding if
+	necessary.
+
+	Support bzip2, lzo and header stripped compression. For lzo use the
+	ffmpeg lzo implementation as liblzo is GPL licensed.
+	
+	Fix zlib decompression.
+
+2008-08-02  Sebastian Dröge  <sebastian.droege@collabora.co.uk>
+
 	* gst/matroska/matroska-mux.c:
 	(gst_matroska_mux_audio_pad_setcaps):
 	Fix muxing of MP3/MP2 with different MPEG versions by calculating the
diff --git a/configure.ac b/configure.ac
index 73fb95cd..ccd9770b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -933,9 +933,9 @@ AG_GST_CHECK_FEATURE(WAVPACK, [wavpack plug-in], wavpack, [
   AC_SUBST(WAVPACK_LIBS)
 ])
 
-dnl *** qtdemux & id3demux prefer to have zlib ***
+dnl *** qtdemux & id3demux & matroska prefer to have zlib ***
 translit(dnm, m, l) AM_CONDITIONAL(USE_ZLIB, true)
-AG_GST_CHECK_FEATURE(ZLIB, [zlib support for id3demux/qtdemux],, [
+AG_GST_CHECK_FEATURE(ZLIB, [zlib support for id3demux/qtdemux/matroska],, [
   AG_GST_CHECK_LIBHEADER(ZLIB,
     z, uncompress,, zlib.h, [
     HAVE_ZLIB="yes"
@@ -944,6 +944,13 @@ AG_GST_CHECK_FEATURE(ZLIB, [zlib support for id3demux/qtdemux],, [
   ])
 ])
 
+dnl *** matroska prefers to have bz2 ***
+translit(dnm, m, l) AM_CONDITIONAL(USE_BZ2, true)
+AG_GST_CHECK_FEATURE(BZ2, [bz2 library for matroska ],, [
+  AG_GST_CHECK_LIBHEADER(BZ2, bz2, BZ2_bzCompress, ,bzlib.h, BZ2_LIBS="-lbz2")
+  AC_SUBST(BZ2_LIBS)
+])
+
 else
 
 dnl not building plugins with external dependencies,
diff --git a/gst/matroska/Makefile.am b/gst/matroska/Makefile.am
index 6c3f2275..6ce6b10d 100644
--- a/gst/matroska/Makefile.am
+++ b/gst/matroska/Makefile.am
@@ -6,7 +6,8 @@ libgstmatroska_la_SOURCES = \
 	matroska.c \
 	matroska-demux.c \
 	matroska-ids.c \
-	matroska-mux.c
+	matroska-mux.c \
+	lzo.c
 
 noinst_HEADERS = \
 	ebml-ids.h \
@@ -14,7 +15,8 @@ noinst_HEADERS = \
 	ebml-write.h \
 	matroska-demux.h \
 	matroska-ids.h \
-	matroska-mux.h
+	matroska-mux.h \
+	lzo.h
 
 libgstmatroska_la_CFLAGS = \
 	$(GST_BASE_CFLAGS) \
@@ -28,5 +30,6 @@ libgstmatroska_la_LIBADD = \
 	-lgstriff-@GST_MAJORMINOR@ \
 	-lgsttag-@GST_MAJORMINOR@ \
 	$(ZLIB_LIBS) \
+	$(BZ2_LIBS) \
 	$(LIBM)
 libgstmatroska_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
diff --git a/gst/matroska/lzo.c b/gst/matroska/lzo.c
new file mode 100644
index 00000000..57982348
--- /dev/null
+++ b/gst/matroska/lzo.c
@@ -0,0 +1,288 @@
+/*
+ * LZO 1x decompression
+ * Copyright (c) 2006 Reimar Doeffinger
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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,
+ * 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
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <gst/gst.h>
+#include <stdlib.h>
+#include <string.h>
+#include "_stdint.h"
+#include "lzo.h"
+
+/*! define if we may write up to 12 bytes beyond the output buffer */
+/* #define OUTBUF_PADDED 1 */
+/*! define if we may read up to 8 bytes beyond the input buffer */
+/* #define INBUF_PADDED 1 */
+typedef struct LZOContext
+{
+  const uint8_t *in, *in_end;
+  uint8_t *out_start, *out, *out_end;
+  int error;
+} LZOContext;
+
+/**
+ * \brief read one byte from input buffer, avoiding overrun
+ * \return byte read
+ */
+static inline int
+get_byte (LZOContext * c)
+{
+  if (c->in < c->in_end)
+    return *c->in++;
+  c->error |= LZO_INPUT_DEPLETED;
+  return 1;
+}
+
+#ifdef INBUF_PADDED
+#define GETB(c) (*(c).in++)
+#else
+#define GETB(c) get_byte(&(c))
+#endif
+
+/**
+ * \brief decode a length value in the coding used by lzo
+ * \param x previous byte value
+ * \param mask bits used from x
+ * \return decoded length value
+ */
+static inline int
+get_len (LZOContext * c, int x, int mask)
+{
+  int cnt = x & mask;
+  if (!cnt) {
+    while (!(x = get_byte (c)))
+      cnt += 255;
+    cnt += mask + x;
+  }
+  return cnt;
+}
+
+/*#define UNALIGNED_LOADSTORE */
+#define BUILTIN_MEMCPY
+#ifdef UNALIGNED_LOADSTORE
+#define COPY2(d, s) *(uint16_t *)(d) = *(uint16_t *)(s);
+#define COPY4(d, s) *(uint32_t *)(d) = *(uint32_t *)(s);
+#elif defined(BUILTIN_MEMCPY)
+#define COPY2(d, s) memcpy(d, s, 2);
+#define COPY4(d, s) memcpy(d, s, 4);
+#else
+#define COPY2(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1];
+#define COPY4(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1]; (d)[2] = (s)[2]; (d)[3] = (s)[3];
+#endif
+
+/**
+ * \brief copy bytes from input to output buffer with checking
+ * \param cnt number of bytes to copy, must be >= 0
+ */
+static inline void
+copy (LZOContext * c, int cnt)
+{
+  register const uint8_t *src = c->in;
+  register uint8_t *dst = c->out;
+  if (cnt > c->in_end - src) {
+    cnt = MAX (c->in_end - src, 0);
+    c->error |= LZO_INPUT_DEPLETED;
+  }
+  if (cnt > c->out_end - dst) {
+    cnt = MAX (c->out_end - dst, 0);
+    c->error |= LZO_OUTPUT_FULL;
+  }
+#if defined(INBUF_PADDED) && defined(OUTBUF_PADDED)
+  COPY4 (dst, src);
+  src += 4;
+  dst += 4;
+  cnt -= 4;
+  if (cnt > 0)
+#endif
+    memcpy (dst, src, cnt);
+  c->in = src + cnt;
+  c->out = dst + cnt;
+}
+
+/**
+ * \brief copy previously decoded bytes to current position
+ * \param back how many bytes back we start
+ * \param cnt number of bytes to copy, must be >= 0
+ *
+ * cnt > back is valid, this will copy the bytes we just copied,
+ * thus creating a repeating pattern with a period length of back.
+ */
+static inline void
+copy_backptr (LZOContext * c, int back, int cnt)
+{
+  register const uint8_t *src = &c->out[-back];
+  register uint8_t *dst = c->out;
+  if (src < c->out_start || src > dst) {
+    c->error |= LZO_INVALID_BACKPTR;
+    return;
+  }
+  if (cnt > c->out_end - dst) {
+    cnt = MAX (c->out_end - dst, 0);
+    c->error |= LZO_OUTPUT_FULL;
+  }
+  if (back == 1) {
+    memset (dst, *src, cnt);
+    dst += cnt;
+  } else {
+#ifdef OUTBUF_PADDED
+    COPY2 (dst, src);
+    COPY2 (dst + 2, src + 2);
+    src += 4;
+    dst += 4;
+    cnt -= 4;
+    if (cnt > 0) {
+      COPY2 (dst, src);
+      COPY2 (dst + 2, src + 2);
+      COPY2 (dst + 4, src + 4);
+      COPY2 (dst + 6, src + 6);
+      src += 8;
+      dst += 8;
+      cnt -= 8;
+    }
+#endif
+    if (cnt > 0) {
+      int blocklen = back;
+      while (cnt > blocklen) {
+        memcpy (dst, src, blocklen);
+        dst += blocklen;
+        cnt -= blocklen;
+        blocklen <<= 1;
+      }
+      memcpy (dst, src, cnt);
+    }
+    dst += cnt;
+  }
+  c->out = dst;
+}
+
+/**
+ * \brief decode LZO 1x compressed data
+ * \param out output buffer
+ * \param outlen size of output buffer, number of bytes left are returned here
+ * \param in input buffer
+ * \param inlen size of input buffer, number of bytes left are returned here
+ * \return 0 on success, otherwise error flags, see lzo.h
+ *
+ * make sure all buffers are appropriately padded, in must provide
+ * LZO_INPUT_PADDING, out must provide LZO_OUTPUT_PADDING additional bytes
+ */
+int
+lzo1x_decode (void *out, int *outlen, const void *in, int *inlen)
+{
+  int state = 0;
+  int x;
+  LZOContext c;
+  c.in = in;
+  c.in_end = (const uint8_t *) in + *inlen;
+  c.out = c.out_start = out;
+  c.out_end = (uint8_t *) out + *outlen;
+  c.error = 0;
+  x = GETB (c);
+  if (x > 17) {
+    copy (&c, x - 17);
+    x = GETB (c);
+    if (x < 16)
+      c.error |= LZO_ERROR;
+  }
+  if (c.in > c.in_end)
+    c.error |= LZO_INPUT_DEPLETED;
+  while (!c.error) {
+    int cnt, back;
+    if (x > 15) {
+      if (x > 63) {
+        cnt = (x >> 5) - 1;
+        back = (GETB (c) << 3) + ((x >> 2) & 7) + 1;
+      } else if (x > 31) {
+        cnt = get_len (&c, x, 31);
+        x = GETB (c);
+        back = (GETB (c) << 6) + (x >> 2) + 1;
+      } else {
+        cnt = get_len (&c, x, 7);
+        back = (1 << 14) + ((x & 8) << 11);
+        x = GETB (c);
+        back += (GETB (c) << 6) + (x >> 2);
+        if (back == (1 << 14)) {
+          if (cnt != 1)
+            c.error |= LZO_ERROR;
+          break;
+        }
+      }
+    } else if (!state) {
+      cnt = get_len (&c, x, 15);
+      copy (&c, cnt + 3);
+      x = GETB (c);
+      if (x > 15)
+        continue;
+      cnt = 1;
+      back = (1 << 11) + (GETB (c) << 2) + (x >> 2) + 1;
+    } else {
+      cnt = 0;
+      back = (GETB (c) << 2) + (x >> 2) + 1;
+    }
+    copy_backptr (&c, back, cnt + 2);
+    state = cnt = x & 3;
+    copy (&c, cnt);
+    x = GETB (c);
+  }
+  *inlen = c.in_end - c.in;
+  if (c.in > c.in_end)
+    *inlen = 0;
+  *outlen = c.out_end - c.out;
+  return c.error;
+}
+
+#ifdef TEST
+#include <stdio.h>
+#include <lzo/lzo1x.h>
+#include "log.h"
+#define MAXSZ (10*1024*1024)
+int
+main (int argc, char *argv[])
+{
+  FILE *in = fopen (argv[1], "rb");
+  uint8_t *orig = av_malloc (MAXSZ + 16);
+  uint8_t *comp = av_malloc (2 * MAXSZ + 16);
+  uint8_t *decomp = av_malloc (MAXSZ + 16);
+  size_t s = fread (orig, 1, MAXSZ, in);
+  lzo_uint clen = 0;
+  long tmp[LZO1X_MEM_COMPRESS];
+  int inlen, outlen;
+  int i;
+  av_log_level = AV_LOG_DEBUG;
+  lzo1x_999_compress (orig, s, comp, &clen, tmp);
+  for (i = 0; i < 300; i++) {
+    START_TIMER inlen = clen;
+    outlen = MAXSZ;
+#ifdef LIBLZO
+    if (lzo1x_decompress_safe (comp, inlen, decomp, &outlen, NULL))
+#elif defined(LIBLZO_UNSAFE)
+    if (lzo1x_decompress (comp, inlen, decomp, &outlen, NULL))
+#else
+    if (lzo1x_decode (decomp, &outlen, comp, &inlen))
+#endif
+      av_log (NULL, AV_LOG_ERROR, "decompression error\n");
+    STOP_TIMER ("lzod")
+  }
+  if (memcmp (orig, decomp, s))
+    av_log (NULL, AV_LOG_ERROR, "decompression incorrect\n");
+  else
+    av_log (NULL, AV_LOG_ERROR, "decompression ok\n");
+  return 0;
+}
+#endif
diff --git a/gst/matroska/lzo.h b/gst/matroska/lzo.h
new file mode 100644
index 00000000..e7795f77
--- /dev/null
+++ b/gst/matroska/lzo.h
@@ -0,0 +1,35 @@
+/*
+ * LZO 1x decompression
+ * copyright (c) 2006 Reimar Doeffinger
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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,
+ * 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
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef FFMPEG_LZO_H
+#define FFMPEG_LZO_H
+
+#define LZO_INPUT_DEPLETED 1
+#define LZO_OUTPUT_FULL 2
+#define LZO_INVALID_BACKPTR 4
+#define LZO_ERROR 8
+
+#define LZO_INPUT_PADDING 8
+#define LZO_OUTPUT_PADDING 12
+
+int lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
+
+#endif /* FFMPEG_LZO_H */
diff --git a/gst/matroska/matroska-demux.c b/gst/matroska/matroska-demux.c
index ee74aeb0..ba67759c 100644
--- a/gst/matroska/matroska-demux.c
+++ b/gst/matroska/matroska-demux.c
@@ -54,6 +54,12 @@
 #include <zlib.h>
 #endif
 
+#ifdef HAVE_BZ2
+#include <bzlib.h>
+#endif
+
+#include "lzo.h"
+
 #include "matroska-demux.h"
 #include "matroska-ids.h"
 
@@ -462,10 +468,6 @@ gst_matroska_demux_read_track_encoding (GstMatroskaDemux * demux,
               G_GUINT64_FORMAT, num);
           ret = GST_FLOW_ERROR;
           break;
-        } else if (num & 0x4) {
-          GST_ERROR_OBJECT (demux, "Unsupported ContentEncodingScope %"
-              G_GUINT64_FORMAT, num);
-          ret = GST_FLOW_ERROR;
         }
 
         GST_DEBUG_OBJECT (demux, "ContentEncodingScope: %" G_GUINT64_FORMAT,
@@ -524,11 +526,6 @@ gst_matroska_demux_read_track_encoding (GstMatroskaDemux * demux,
                     G_GUINT64_FORMAT, num);
                 ret = GST_FLOW_ERROR;
                 break;
-              } else if (num != 0) {
-                GST_ERROR_OBJECT (demux, "Unsupported ContentCompAlgo %"
-                    G_GUINT64_FORMAT, num);
-                ret = GST_FLOW_ERROR;
-                break;
               }
               GST_DEBUG_OBJECT (demux, "ContentCompAlgo: %" G_GUINT64_FORMAT,
                   num);
@@ -596,6 +593,317 @@ gst_matroska_demux_read_track_encoding (GstMatroskaDemux * demux,
   return ret;
 }
 
+static gboolean
+gst_matroska_decompress_data (GstMatroskaTrackEncoding * enc,
+    guint8 ** data_out, guint * size_out,
+    GstMatroskaTrackCompressionAlgorithm algo)
+{
+  guint8 *new_data = NULL;
+  guint new_size = 0;
+
+  guint8 *data = *data_out;
+  guint size = *size_out;
+
+  gboolean ret = TRUE;
+
+  if (algo == GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_ZLIB) {
+#ifdef HAVE_ZLIB
+    /* zlib encoded data */
+    z_stream zstream;
+    guint orig_size;
+    int result;
+
+    orig_size = size;
+    zstream.zalloc = (alloc_func) 0;
+    zstream.zfree = (free_func) 0;
+    zstream.opaque = (voidpf) 0;
+    if (inflateInit (&zstream) != Z_OK) {
+      GST_WARNING ("zlib initialization failed.");
+      ret = FALSE;
+      goto out;
+    }
+    zstream.next_in = (Bytef *) data;
+    zstream.avail_in = orig_size;
+    new_size = orig_size;
+    new_data = g_malloc (new_size);
+    zstream.avail_out = new_size;
+    zstream.next_out = (Bytef *) new_data;
+
+    do {
+      result = inflate (&zstream, Z_NO_FLUSH);
+      if (result != Z_OK && result != Z_STREAM_END) {
+        GST_WARNING ("zlib decompression failed.");
+        g_free (new_data);
+        inflateEnd (&zstream);
+        break;
+      }
+      new_size += 4000;
+      new_data = g_realloc (new_data, new_size);
+      zstream.next_out = (Bytef *) (new_data + zstream.total_out);
+      zstream.avail_out += 4000;
+    } while (zstream.avail_in != 0 && result != Z_STREAM_END);
+
+    if (result != Z_STREAM_END) {
+      ret = FALSE;
+      goto out;
+    } else {
+      new_size = zstream.total_out;
+      inflateEnd (&zstream);
+    }
+#else
+    GST_WARNING ("zlib encoded tracks not supported.");
+    ret = FALSE;
+    goto out;
+#endif
+  } else if (algo == GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_BZLIB) {
+#ifdef HAVE_BZ2
+    /* bzip2 encoded data */
+    bz_stream bzstream;
+    guint orig_size;
+    int result;
+
+    bzstream.bzalloc = NULL;
+    bzstream.bzfree = NULL;
+    bzstream.opaque = NULL;
+    orig_size = size;
+
+    if ((result = BZ2_bzDecompressInit (&bzstream, 0, 0)) != BZ_OK) {
+      GST_WARNING ("bzip2 initialization failed.");
+      ret = FALSE;
+      goto out;
+    }
+
+    bzstream.next_in = (char *) data;
+    bzstream.avail_in = orig_size;
+    new_size = orig_size;
+    new_data = g_malloc (new_size);
+    bzstream.avail_out = new_size;
+    bzstream.next_out = (char *) new_data;
+
+    do {
+      result = BZ2_bzDecompress (&bzstream);
+      if (result != BZ_OK && result != BZ_STREAM_END) {
+        GST_WARNING ("bzip2 decompression failed.");
+        g_free (new_data);
+        BZ2_bzDecompressEnd (&bzstream);
+        break;
+      }
+      new_size += 4000;
+      new_data = g_realloc (new_data, new_size);
+      bzstream.next_out = (char *) (new_data + bzstream.total_out_lo32);
+      bzstream.avail_out += 4000;
+    } while (bzstream.avail_in != 0 && result != BZ_STREAM_END);
+
+    if (result != BZ_STREAM_END) {
+      ret = FALSE;
+      goto out;
+    } else {
+      new_size = bzstream.total_out_lo32;
+      BZ2_bzDecompressEnd (&bzstream);
+    }
+#else
+    GST_WARNING ("bzip2 encoded tracks not supported.");
+    ret = FALSE;
+    goto out;
+#endif
+  } else if (algo == GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_LZO1X) {
+    /* lzo encoded data */
+    int result;
+    int orig_size, out_size;
+
+    orig_size = size;
+    out_size = size;
+    new_size = size;
+    new_data = g_malloc (new_size);
+
+    do {
+      orig_size = size;
+      out_size = new_size;
+
+      result = lzo1x_decode (new_data, &out_size, data, &orig_size);
+
+      if (orig_size > 0) {
+        new_size += 4000;
+        new_data = g_realloc (new_data, new_size);
+      }
+    } while (orig_size > 0 && result == LZO_OUTPUT_FULL);
+
+    new_size -= out_size;
+
+    if (result != LZO_OUTPUT_FULL) {
+      GST_WARNING ("lzo decompression failed");
+      g_free (new_data);
+
+      ret = FALSE;
+      goto out;
+    }
+
+  } else if (algo == GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_HEADERSTRIP) {
+    /* header stripped encoded data */
+    if (enc->comp_settings_length > 0) {
+      new_data = g_malloc (size + enc->comp_settings_length);
+      new_size = size + enc->comp_settings_length;
+
+      memcpy (new_data, enc->comp_settings, enc->comp_settings_length);
+      memcpy (new_data + enc->comp_settings_length, data, size);
+    }
+  } else {
+    g_assert_not_reached ();
+  }
+
+out:
+
+  if (!ret) {
+    *data_out = NULL;
+    *size_out = 0;
+  } else {
+    *data_out = new_data;
+    *size_out = new_size;
+  }
+
+  return ret;
+}
+
+static gboolean
+gst_matroska_decode_data (GArray * encodings, guint8 ** data_out,
+    guint * size_out, GstMatroskaTrackEncodingScope scope, gboolean free)
+{
+  guint8 *data;
+  guint size;
+  gboolean ret = TRUE;
+  gint i;
+
+  g_return_val_if_fail (encodings != NULL, FALSE);
+  g_return_val_if_fail (data_out != NULL && *data_out != NULL, FALSE);
+  g_return_val_if_fail (size_out != NULL, FALSE);
+
+  data = *data_out;
+  size = *size_out;
+
+  for (i = 0; i < encodings->len; i++) {
+    GstMatroskaTrackEncoding *enc =
+        &g_array_index (encodings, GstMatroskaTrackEncoding, i);
+    guint8 *new_data = NULL;
+    guint new_size = 0;
+
+    if ((enc->scope & scope) == 0)
+      continue;
+
+    /* Encryption not supported yet */
+    if (enc->type != 0) {
+      ret = FALSE;
+      break;
+    }
+
+    new_data = data;
+    new_size = size;
+
+    ret =
+        gst_matroska_decompress_data (enc, &new_data, &new_size,
+        enc->comp_algo);
+
+    if (!ret)
+      break;
+
+    if ((data == *data_out && free) || (data != *data_out))
+      g_free (data);
+
+    data = new_data;
+    size = new_size;
+  }
+
+  if (!ret) {
+    if ((data == *data_out && free) || (data != *data_out))
+      g_free (data);
+
+    *data_out = NULL;
+    *size_out = 0;
+  } else {
+    *data_out = data;
+    *size_out = size;
+  }
+
+  return ret;
+}
+
+static GstBuffer *
+gst_matroska_decode_buffer (GstMatroskaTrackContext * context, GstBuffer * buf)
+{
+  guint8 *data;
+  guint size;
+  GstBuffer *new_buf;
+
+  g_return_val_if_fail (GST_IS_BUFFER (buf), NULL);
+
+  data = GST_BUFFER_DATA (buf);
+  size = GST_BUFFER_SIZE (buf);
+
+  g_return_val_if_fail (data != NULL && size > 0, buf);
+
+  if (gst_matroska_decode_data (context->encodings, &data, &size,
+          GST_MATROSKA_TRACK_ENCODING_SCOPE_FRAME, FALSE)) {
+    new_buf = gst_buffer_new ();
+    GST_BUFFER_MALLOCDATA (new_buf) = (guint8 *) data;
+    GST_BUFFER_DATA (new_buf) = (guint8 *) data;
+    GST_BUFFER_SIZE (new_buf) = size;
+
+    gst_buffer_unref (buf);
+    buf = new_buf;
+
+    return buf;
+  } else {
+    gst_buffer_unref (buf);
+    return NULL;
+  }
+}
+
+static GstFlowReturn
+gst_matroska_decode_content_encodings (GArray * encodings)
+{
+  gint i;
+
+  if (encodings == NULL)
+    return GST_FLOW_OK;
+
+  for (i = 0; i < encodings->len; i++) {
+    GstMatroskaTrackEncoding *enc =
+        &g_array_index (encodings, GstMatroskaTrackEncoding, i);
+    GstMatroskaTrackEncoding *enc2;
+    guint8 *data = NULL;
+    guint size;
+
+    if ((enc->
+            scope & GST_MATROSKA_TRACK_ENCODING_SCOPE_NEXT_CONTENT_ENCODING) ==
+        0)
+      continue;
+
+    /* Encryption not supported yet */
+    if (enc->type != 0)
+      return GST_FLOW_ERROR;
+
+    if (i + 1 >= encodings->len)
+      return GST_FLOW_ERROR;
+
+    enc2 = &g_array_index (encodings, GstMatroskaTrackEncoding, i + 1);
+
+    if (enc->comp_settings_length == 0)
+      continue;
+
+    data = enc->comp_settings;
+    size = enc->comp_settings_length;
+
+    if (!gst_matroska_decompress_data (enc, &data, &size, enc->comp_algo))
+      return GST_FLOW_ERROR;
+
+    g_free (enc->comp_settings);
+
+    enc->comp_settings = data;
+    enc->comp_settings_length = size;
+  }
+
+  return GST_FLOW_OK;
+}
+
 static GstFlowReturn
 gst_matroska_demux_read_track_encodings (GstMatroskaDemux * demux,
     GstMatroskaTrackContext * context)
@@ -648,9 +956,7 @@ gst_matroska_demux_read_track_encodings (GstMatroskaDemux * demux,
   g_array_sort (context->encodings,
       (GCompareFunc) gst_matroska_demux_encoding_cmp);
 
-  /* TODO: Decompress & decrypt ContentEncodings if necessary */
-
-  return ret;
+  return gst_matroska_decode_content_encodings (context->encodings);
 }
 
 static gboolean
@@ -1355,7 +1661,16 @@ gst_matroska_demux_add_stream (GstMatroskaDemux * demux)
 
   DEBUG_ELEMENT_STOP (demux, ebml, "TrackEntry", ret);
 
-  /* TODO: decompress/decrypt codec private if necessary */
+  /* Decode codec private data if necessary */
+  if (context->encodings && context->encodings->len > 0 && context->codec_priv
+      && context->codec_priv_size > 0) {
+    if (!gst_matroska_decode_data (context->encodings,
+            (guint8 **) & context->codec_priv, &context->codec_priv_size,
+            GST_MATROSKA_TRACK_ENCODING_SCOPE_CODEC_DATA, TRUE)) {
+      GST_WARNING_OBJECT (demux, "Decoding codec private data failed");
+      ret = GST_FLOW_ERROR;
+    }
+  }
 
   if (context->type == 0 || context->codec_id == NULL || (ret != GST_FLOW_OK
           && ret != GST_FLOW_UNEXPECTED)) {
@@ -3496,100 +3811,6 @@ gst_matroska_demux_check_subtitle_buffer (GstElement * element,
   return GST_FLOW_OK;
 }
 
-static GstBuffer *
-gst_matroska_decode_buffer (GstMatroskaTrackContext * context, GstBuffer * buf)
-{
-  gint i;
-
-  g_assert (context->encodings != NULL);
-
-  for (i = 0; i < context->encodings->len; i++) {
-    GstMatroskaTrackEncoding *enc;
-    guint8 *new_data = NULL;
-    guint new_size = 0;
-    GstBuffer *new_buf;
-
-    enc = &g_array_index (context->encodings, GstMatroskaTrackEncoding, i);
-
-    /* Currently only compression is supported */
-    if (enc->type != 0)
-      break;
-
-    /* FIXME: use enc->scope ! only necessary to decode buffer if scope & 0x1 */
-
-    if (enc->comp_algo == 0) {
-#ifdef HAVE_ZLIB
-      /* zlib encoded track */
-      z_stream zstream;
-      guint orig_size;
-      int result;
-
-      orig_size = GST_BUFFER_SIZE (buf);
-      zstream.zalloc = (alloc_func) 0;
-      zstream.zfree = (free_func) 0;
-      zstream.opaque = (voidpf) 0;
-      if (inflateInit (&zstream) != Z_OK) {
-        GST_WARNING ("zlib initialization failed.");
-        break;
-      }
-      zstream.next_in = (Bytef *) GST_BUFFER_DATA (buf);
-      zstream.avail_in = orig_size;
-      new_size = orig_size;
-      new_data = g_malloc (new_size);
-      zstream.avail_out = new_size;
-      /* FIXME: not exactly fast, right? */
-      do {
-        new_size += 4000;
-        new_data = g_realloc (new_data, new_size);
-        zstream.next_out = (Bytef *) (new_data + zstream.total_out);
-        result = inflate (&zstream, Z_NO_FLUSH);
-        if (result != Z_OK && result != Z_STREAM_END) {
-          GST_WARNING ("zlib decompression failed.");
-          g_free (new_data);
-          inflateEnd (&zstream);
-          break;
-        }
-        zstream.avail_out += 4000;
-      } while (zstream.avail_out == 4000 &&
-          zstream.avail_in != 0 && result != Z_STREAM_END);
-
-      new_size = zstream.total_out;
-      inflateEnd (&zstream);
-#else
-      GST_WARNING ("zlib encoded tracks not supported.");
-      break;
-#endif
-/* FIXME: add bzip/lzo support, what is header stripped?
- * it's insane and requires deeper knowledge of the used codec
- */
-    } else if (enc->comp_algo == 1) {
-      GST_WARNING ("BZIP encoded tracks not supported.");
-      break;
-    } else if (enc->comp_algo == 2) {
-      GST_WARNING ("LZO encoded tracks not supported.");
-      break;
-    } else if (enc->comp_algo == 3) {
-      GST_WARNING ("Header-stripped tracks not supported.");
-      break;
-    } else {
-      g_assert_not_reached ();
-    }
-
-    g_assert (new_data != NULL);
-
-    new_buf = gst_buffer_new ();
-    GST_BUFFER_MALLOCDATA (new_buf) = (guint8 *) new_data;
-    GST_BUFFER_DATA (new_buf) = (guint8 *) new_data;
-    GST_BUFFER_SIZE (new_buf) = new_size;
-    gst_buffer_copy_metadata (new_buf, buf, GST_BUFFER_COPY_TIMESTAMPS);
-
-    gst_buffer_unref (buf);
-    buf = new_buf;
-  }
-
-  return buf;
-}
-
 static GstFlowReturn
 gst_matroska_demux_parse_blockgroup_or_simpleblock (GstMatroskaDemux * demux,
     guint64 cluster_time, gboolean is_simpleblock)
@@ -3804,7 +4025,17 @@ gst_matroska_demux_parse_blockgroup_or_simpleblock (GstMatroskaDemux * demux,
         g_free (stream->codec_state);
         stream->codec_state = data;
         stream->codec_state_size = data_len;
-        /* TODO: decompress/decrypt if necessary */
+
+        /* Decode if necessary */
+        if (stream->encodings && stream->encodings->len > 0
+            && stream->codec_state && stream->codec_state_size > 0) {
+          if (!gst_matroska_decode_data (stream->encodings,
+                  (guint8 **) & stream->codec_state, &stream->codec_state_size,
+                  GST_MATROSKA_TRACK_ENCODING_SCOPE_CODEC_DATA, TRUE)) {
+            GST_WARNING_OBJECT (demux, "Decoding codec state failed");
+          }
+        }
+
         GST_DEBUG_OBJECT (demux, "CodecState of %u bytes",
             stream->codec_state_size);
         break;
@@ -3880,6 +4111,11 @@ gst_matroska_demux_parse_blockgroup_or_simpleblock (GstMatroskaDemux * demux,
       if (stream->encodings != NULL && stream->encodings->len > 0)
         sub = gst_matroska_decode_buffer (stream, sub);
 
+      if (sub == NULL) {
+        GST_WARNING_OBJECT (demux, "Decoding buffer failed");
+        goto next_lace;
+      }
+
       GST_BUFFER_TIMESTAMP (sub) = lace_time;
 
       if (lace_time != GST_CLOCK_TIME_NONE) {
@@ -3950,6 +4186,7 @@ gst_matroska_demux_parse_blockgroup_or_simpleblock (GstMatroskaDemux * demux,
       /* combine flows */
       ret = gst_matroska_demux_combine_flows (demux, stream, ret);
 
+    next_lace:
       size -= lace_size[n];
       if (lace_time != GST_CLOCK_TIME_NONE)
         lace_time += duration / laces;
diff --git a/gst/matroska/matroska-ids.h b/gst/matroska/matroska-ids.h
index c6c1852a..8a73d37a 100644
--- a/gst/matroska/matroska-ids.h
+++ b/gst/matroska/matroska-ids.h
@@ -554,6 +554,19 @@ typedef struct _Wavpack4Header {
   guint32 crc;           /* crc for actual decoded data                    */
 } Wavpack4Header;
 
+typedef enum {
+  GST_MATROSKA_TRACK_ENCODING_SCOPE_FRAME = (1<<0),
+  GST_MATROSKA_TRACK_ENCODING_SCOPE_CODEC_DATA = (1<<1),
+  GST_MATROSKA_TRACK_ENCODING_SCOPE_NEXT_CONTENT_ENCODING = (1<<2)
+} GstMatroskaTrackEncodingScope;
+
+typedef enum {
+  GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_ZLIB = 0,
+  GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_BZLIB = 1,
+  GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_LZO1X = 2,
+  GST_MATROSKA_TRACK_COMPRESSION_ALGORITHM_HEADERSTRIP = 3
+} GstMatroskaTrackCompressionAlgorithm;
+
 typedef struct _GstMatroskaTrackEncoding {
   guint   order;
   guint   scope     : 3;