}
}
-/* EBML typefind helper */
-static gboolean
-ebml_check_header (GstTypeFind * tf, const gchar * doctype, int doctype_len)
+/*** Matroska/WebM ***/
+
+#define EBML_HEADER 0x1A45DFA3
+#define EBML_VERSION 0x4286
+#define EBML_DOCTYPE 0x4282
+#define EBML_DOCTYPE_VERSION 0x4287
+#define MATROSKA_SEGMENT 0x18538067
+#define MATROSKA_CLUSTER 0x1F43B675
+#define MATROSKA_TRACKS 0x1654AE6B
+#define MATROSKA_TRACK_ENTRY 0xAE
+#define MATROSKA_TRACK_TYPE 0x83
+#define MATROSKA_STEREO_MODE 0x53B8
+
+#define EBML_MAX_LEN (2 * 1024 * 1024)
+
+typedef enum
{
- /* 4 bytes for EBML ID, 1 byte for header length identifier */
- const guint8 *data = gst_type_find_peek (tf, 0, 4 + 1);
- gint len_mask = 0x80, size = 1, n = 1, total;
+ EBML_DOCTYPE_UNKNOWN = 0,
+ EBML_DOCTYPE_MATROSKA,
+ EBML_DOCTYPE_WEBM
+} GstEbmlDocType;
- if (!data)
- return FALSE;
+typedef struct
+{
+ GstEbmlDocType doctype;
+ guint audio;
+ guint video;
+ guint other;
+ guint video_stereo;
+ guint chunks;
+ guint tracks_ok; /* if we've seen and fully parsed the TRACKS element */
+} GstMatroskaInfo;
- /* ebml header? */
- if (data[0] != 0x1A || data[1] != 0x45 || data[2] != 0xDF || data[3] != 0xA3)
- return FALSE;
+static inline guint
+ebml_read_chunk_header (GstTypeFind * tf, DataScanCtx * c, guint max_size,
+ guint32 * id, guint64 * size)
+{
+ guint64 mask;
+ guint msbit_set, i, len, id_len;
+
+ if (c->size < 12 || max_size < 1)
+ return 0;
- /* length of header */
- total = data[4];
- while (size <= 8 && !(total & len_mask)) {
- size++;
- len_mask >>= 1;
+ /* element ID */
+ *id = c->data[0];
+ if ((c->data[0] & 0x80) == 0x80) {
+ id_len = 1;
+ } else if ((c->data[0] & 0xC0) == 0x40) {
+ id_len = 2;
+ } else if ((c->data[0] & 0xE0) == 0x20) {
+ id_len = 3;
+ } else if ((c->data[0] & 0xF0) == 0x10) {
+ id_len = 4;
+ } else {
+ return 0;
}
- if (size > 8)
- return FALSE;
- total &= (len_mask - 1);
- while (n < size)
- total = (total << 8) | data[4 + n++];
- /* get new data for full header, 4 bytes for EBML ID,
- * EBML length tag and the actual header */
- data = gst_type_find_peek (tf, 0, 4 + size + total);
- if (!data)
+ if (max_size < id_len)
+ return 0;
+
+ for (i = 1; i < id_len; ++i) {
+ *id = (*id << 8) | c->data[i];
+ }
+
+ data_scan_ctx_advance (tf, c, id_len);
+ max_size -= id_len;
+
+ /* size */
+ if (max_size < 1 || c->data[0] == 0)
+ return 0;
+
+ msbit_set = g_bit_nth_msf (c->data[0], 8);
+ mask = ((1 << msbit_set) - 1);
+ *size = c->data[0] & mask;
+ len = 7 - msbit_set;
+
+ if (max_size < 1 + len)
+ return 0;
+ for (i = 0; i < len; ++i) {
+ mask = (mask << 8) | 0xff;
+ *size = (*size << 8) | c->data[1 + i];
+ }
+
+ data_scan_ctx_advance (tf, c, 1 + len);
+
+ /* undefined/unknown size? (all bits 1) */
+ if (*size == mask) {
+ /* allow unknown size for SEGMENT chunk, bail out otherwise */
+ if (*id == MATROSKA_SEGMENT)
+ *size = G_MAXUINT64;
+ else
+ return 0;
+ }
+
+ return id_len + (1 + len);
+}
+
+static gboolean
+ebml_parse_chunk (GstTypeFind * tf, DataScanCtx * ctx, guint32 chunk_id,
+ guint chunk_size, GstMatroskaInfo * info, guint depth)
+{ /* FIXME: make sure input size is clipped to 32 bit */
+ static const gchar SPACES[] = " ";
+ DataScanCtx c = *ctx;
+ guint64 element_size;
+ guint32 id, hdr_len;
+
+ if (depth >= 8) /* keep SPACES large enough for depth */
return FALSE;
- /* only check doctype if asked to do so */
- if (doctype == NULL || doctype_len == 0)
- return TRUE;
+ while (chunk_size > 0) {
+ if (c.offset > EBML_MAX_LEN || !data_scan_ctx_ensure_data (tf, &c, 64))
+ return FALSE;
- /* the header must contain the doctype. For now, we don't parse the
- * whole header but simply check for the availability of that array
- * of characters inside the header. Not fully fool-proof, but good
- * enough. */
- for (n = 4 + size; n <= 4 + size + total - doctype_len; n++)
- if (!memcmp (&data[n], doctype, doctype_len))
- return TRUE;
+ hdr_len = ebml_read_chunk_header (tf, &c, chunk_size, &id, &element_size);
+ if (hdr_len == 0)
+ return FALSE;
- return FALSE;
+ g_assert (hdr_len <= chunk_size);
+ chunk_size -= hdr_len;
+
+ if (element_size > chunk_size)
+ return FALSE;
+
+ GST_DEBUG ("%s %08x, size %" G_GUINT64_FORMAT " / %" G_GUINT64_FORMAT,
+ SPACES + sizeof (SPACES) - 1 - (2 * depth), id, element_size,
+ hdr_len + element_size);
+
+ if (!data_scan_ctx_ensure_data (tf, &c, element_size)) {
+ GST_DEBUG ("not enough data");
+ return FALSE;
+ }
+
+ switch (id) {
+ case EBML_DOCTYPE:
+ if (element_size >= 8 && memcmp (c.data, "matroska", 8) == 0)
+ info->doctype = EBML_DOCTYPE_MATROSKA;
+ else if (element_size >= 4 && memcmp (c.data, "webm", 4) == 0)
+ info->doctype = EBML_DOCTYPE_WEBM;
+ break;
+ case MATROSKA_SEGMENT:
+ GST_LOG ("parsing segment");
+ ebml_parse_chunk (tf, &c, id, element_size, info, depth + 1);
+ GST_LOG ("parsed segment, done");
+ return FALSE;
+ case MATROSKA_TRACKS:
+ GST_LOG ("parsing tracks");
+ info->tracks_ok =
+ ebml_parse_chunk (tf, &c, id, element_size, info, depth + 1);
+ GST_LOG ("parsed tracks: %s, done (after %" G_GUINT64_FORMAT " bytes)",
+ info->tracks_ok ? "ok" : "FAIL", c.offset + element_size);
+ return FALSE;
+ case MATROSKA_TRACK_ENTRY:
+ GST_LOG ("parsing track entry");
+ if (!ebml_parse_chunk (tf, &c, id, element_size, info, depth + 1))
+ return FALSE;
+ break;
+ case MATROSKA_TRACK_TYPE:{
+ guint type = 0, i;
+
+ /* is supposed to always be 1-byte, but not everyone's following that */
+ for (i = 0; i < element_size; ++i)
+ type = (type << 8) | c.data[i];
+
+ GST_DEBUG ("%s track type %u",
+ SPACES + sizeof (SPACES) - 1 - (2 * depth), type);
+
+ if (type == 1)
+ ++info->video;
+ else if (c.data[0] == 2)
+ ++info->audio;
+ else
+ ++info->other;
+ break;
+ }
+ case MATROSKA_STEREO_MODE:
+ ++info->video_stereo;
+ break;
+ case MATROSKA_CLUSTER:
+ GST_WARNING ("cluster, bailing out (should've found tracks by now)");
+ return FALSE;
+ default:
+ break;
+ }
+ data_scan_ctx_advance (tf, &c, element_size);
+ chunk_size -= element_size;
+ ++info->chunks;
+ }
+
+ return TRUE;
}
-/*** video/x-matroska ***/
static GstStaticCaps matroska_caps = GST_STATIC_CAPS ("video/x-matroska");
#define MATROSKA_CAPS (gst_static_caps_get(&matroska_caps))
static void
matroska_type_find (GstTypeFind * tf, gpointer ununsed)
{
- if (ebml_check_header (tf, "matroska", 8))
- gst_type_find_suggest (tf, GST_TYPE_FIND_MAXIMUM, MATROSKA_CAPS);
- else if (ebml_check_header (tf, NULL, 0))
- gst_type_find_suggest (tf, GST_TYPE_FIND_LIKELY, MATROSKA_CAPS);
-}
+ GstTypeFindProbability prob;
+ GstMatroskaInfo info = { 0, };
+ const gchar *type_name;
+ DataScanCtx c = { 0, NULL, 0 };
+ gboolean is_audio;
+ guint64 size;
+ guint32 id, hdr_len;
-/*** video/webm ***/
-static GstStaticCaps webm_caps = GST_STATIC_CAPS ("video/webm");
+ if (!data_scan_ctx_ensure_data (tf, &c, 64))
+ return;
-#define WEBM_CAPS (gst_static_caps_get(&webm_caps))
-static void
-webm_type_find (GstTypeFind * tf, gpointer ununsed)
-{
- if (ebml_check_header (tf, "webm", 4))
- gst_type_find_suggest (tf, GST_TYPE_FIND_MAXIMUM, WEBM_CAPS);
+ if (GST_READ_UINT32_BE (c.data) != EBML_HEADER)
+ return;
+
+ while (c.offset < EBML_MAX_LEN && data_scan_ctx_ensure_data (tf, &c, 64)) {
+ hdr_len = ebml_read_chunk_header (tf, &c, c.size, &id, &size);
+ if (hdr_len == 0)
+ return;
+
+ GST_INFO ("=== top-level chunk %08x, size %" G_GUINT64_FORMAT
+ " / %" G_GUINT64_FORMAT, id, size, size + hdr_len);
+
+ if (!ebml_parse_chunk (tf, &c, id, size, &info, 0))
+ break;
+ data_scan_ctx_advance (tf, &c, size);
+ GST_INFO ("=== done with chunk %08x", id);
+ if (id == MATROSKA_SEGMENT)
+ break;
+ }
+
+ GST_INFO ("audio=%u video=%u other=%u chunks=%u doctype=%d all_tracks=%d",
+ info.audio, info.video, info.other, info.chunks, info.doctype,
+ info.tracks_ok);
+
+ /* perhaps we should bail out if tracks_ok is FALSE and wait for more data?
+ * (we would need new API to signal this properly and prevent other
+ * typefinders from taking over the decision then) */
+ is_audio = (info.audio > 0 && info.video == 0 && info.other == 0);
+
+ if (info.doctype == EBML_DOCTYPE_WEBM) {
+ type_name = (is_audio) ? "audio/webm" : "video/webm";
+ } else if (info.video > 0 && info.video_stereo) {
+ type_name = "video/x-matroska-3d";
+ } else {
+ type_name = (is_audio) ? "audio/x-matroska" : "video/x-matroska";
+ }
+
+ if (info.doctype == EBML_DOCTYPE_UNKNOWN)
+ prob = GST_TYPE_FIND_LIKELY;
+ else
+ prob = GST_TYPE_FIND_MAXIMUM;
+
+ gst_type_find_suggest_simple (tf, prob, type_name, NULL);
}
/*** application/mxf ***/
TYPE_FIND_REGISTER (plugin, "image/x-portable-pixmap", GST_RANK_SECONDARY,
pnm_type_find, "pnm,ppm,pgm,pbm", PNM_CAPS, NULL, NULL);
TYPE_FIND_REGISTER (plugin, "video/x-matroska", GST_RANK_PRIMARY,
- matroska_type_find, "mkv,mka", MATROSKA_CAPS, NULL, NULL);
- TYPE_FIND_REGISTER (plugin, "video/webm", GST_RANK_PRIMARY, webm_type_find,
- "webm", WEBM_CAPS, NULL, NULL);
+ matroska_type_find, "mkv,mka,mk3d,webm", MATROSKA_CAPS, NULL, NULL);
TYPE_FIND_REGISTER (plugin, "application/mxf", GST_RANK_PRIMARY,
mxf_type_find, "mxf", MXF_CAPS, NULL, NULL);
TYPE_FIND_REGISTER_START_WITH (plugin, "video/x-mve", GST_RANK_SECONDARY,
projects / platform / upstream / gstreamer.git / commitdiff