[FFmpeg-devel] [PATCH] Adds support parsing the QuickTime Metadata Keys.
Tinglin Liu
tinglin at google.com
Fri Oct 23 00:04:46 CEST 2015
The Apple dev specification:
https://developer.apple.com/library/mac/documentation/QuickTime/QTFF/Metadata/Metadata.html
Basically the structure is like:
|--meta
|----hdlr
|----keys
|----ilst
1) The handler type in the metadata handler atom is ‘mdta’.
2) The key and value are stored separately for each key-value pair. 'keys' atom stores the key table, while 'ilst' atom stores the values corresponding to the indices in the key table.
---
libavformat/isom.h | 3 ++
libavformat/mov.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++----
2 files changed, 90 insertions(+), 6 deletions(-)
diff --git a/libavformat/isom.h b/libavformat/isom.h
index 6e921c0..dba30a2 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -177,6 +177,9 @@ typedef struct MOVContext {
int64_t duration; ///< duration of the longest track
int found_moov; ///< 'moov' atom has been found
int found_mdat; ///< 'mdat' atom has been found
+ int found_hdlr_mdta; ///< 'hdlr' atom with type 'mdta' has been found
+ char **meta_keys;
+ unsigned meta_keys_count;
DVDemuxContext *dv_demux;
AVFormatContext *dv_fctx;
int isom; ///< 1 if file is ISO Media (mp4/3gp)
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 7c90d40..c7905a1 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -265,6 +265,7 @@ static int mov_read_udta_string(MOVContext *c, AVIOContext *pb, MOVAtom atom)
uint32_t data_type = 0, str_size, str_size_alloc;
int (*parse)(MOVContext*, AVIOContext*, unsigned, const char*) = NULL;
int raw = 0;
+ int num = 0;
switch (atom.type) {
case MKTAG( '@','P','R','M'): key = "premiere_version"; raw = 1; break;
@@ -368,6 +369,15 @@ retry:
av_log(c->fc, AV_LOG_ERROR, "Error parsing cover art.\n");
}
return ret;
+ } else if (!key && c->found_hdlr_mdta && c->meta_keys) {
+ uint32_t index = AV_RB32(&atom.type);
+ if (index < c->meta_keys_count) {
+ key = c->meta_keys[index];
+ } else {
+ av_log(c->fc, AV_LOG_WARNING,
+ "The index of 'data' is out of range: %d >= %d.\n",
+ index, c->meta_keys_count);
+ }
}
} else return 0;
} else if (atom.size > 4 && key && !c->itunes_metadata && !raw) {
@@ -394,8 +404,10 @@ retry:
if (atom.size < 0 || str_size >= INT_MAX/2)
return AVERROR_INVALIDDATA;
+ // Allocates enough space if data_type is a float32 number, otherwise
// worst-case requirement for output string in case of utf8 coded input
- str_size_alloc = (raw ? str_size : str_size * 2) + 1;
+ num = (data_type == 23);
+ str_size_alloc = (num ? 512 : (raw ? str_size : str_size * 2)) + 1;
str = av_mallocz(str_size_alloc);
if (!str)
return AVERROR(ENOMEM);
@@ -405,6 +417,14 @@ retry:
else {
if (!raw && (data_type == 3 || (data_type == 0 && (langcode < 0x400 || langcode == 0x7fff)))) { // MAC Encoded
mov_read_mac_string(c, pb, str_size, str, str_size_alloc);
+ } else if (data_type == 23 && str_size >= 4) { // BE float32
+ union av_intfloat32 val;
+ val.i = avio_rb32(pb);
+ if (snprintf(str, str_size_alloc, "%f", val.f) >= str_size_alloc) {
+ av_log(c->fc, AV_LOG_ERROR,
+ "Failed to store the float32 number (0x%x) in string.\n", val.i);
+ return AVERROR_INVALIDDATA;
+ }
} else {
int ret = ffio_read_size(pb, str, str_size);
if (ret < 0) {
@@ -599,11 +619,6 @@ static int mov_read_hdlr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
char *title_str;
int ret;
- if (c->fc->nb_streams < 1) // meta before first trak
- return 0;
-
- st = c->fc->streams[c->fc->nb_streams-1];
-
avio_r8(pb); /* version */
avio_rb24(pb); /* flags */
@@ -614,6 +629,15 @@ static int mov_read_hdlr(MOVContext *c, AVIOContext *pb, MOVAtom atom)
av_log(c->fc, AV_LOG_TRACE, "ctype= %.4s (0x%08x)\n", (char*)&ctype, ctype);
av_log(c->fc, AV_LOG_TRACE, "stype= %.4s\n", (char*)&type);
+ if (c->fc->nb_streams < 1) { // meta before first trak
+ if (type == MKTAG('m','d','t','a')) {
+ c->found_hdlr_mdta = 1;
+ }
+ return 0;
+ }
+
+ st = c->fc->streams[c->fc->nb_streams-1];
+
if (type == MKTAG('v','i','d','e'))
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
else if (type == MKTAG('s','o','u','n'))
@@ -3127,6 +3151,48 @@ static int mov_read_ilst(MOVContext *c, AVIOContext *pb, MOVAtom atom)
return ret;
}
+static int mov_read_keys(MOVContext *c, AVIOContext *pb, MOVAtom atom)
+{
+ uint32_t count;
+ uint32_t i;
+
+ if (atom.size < 8)
+ return 0;
+
+ avio_skip(pb, 4);
+ count = avio_rb32(pb);
+ if (count > UINT_MAX / sizeof(*c->meta_keys)) {
+ av_log(c->fc, AV_LOG_ERROR,
+ "The 'keys' atom with the invalid key count: %d\n", count);
+ return AVERROR_INVALIDDATA;
+ }
+
+ c->meta_keys_count = count + 1;
+ c->meta_keys = av_mallocz(c->meta_keys_count * sizeof(*c->meta_keys));
+ if (!c->meta_keys)
+ return AVERROR(ENOMEM);
+
+ for (i = 1; i <= count; ++i) {
+ uint32_t key_size = avio_rb32(pb);
+ uint32_t type = avio_rl32(pb);
+ if (key_size < 8) {
+ av_log(c->fc, AV_LOG_ERROR,
+ "The key# %d in meta has invalid size: %d\n", i, key_size);
+ return AVERROR_INVALIDDATA;
+ }
+ key_size -= 8;
+ if (type != MKTAG('m','d','t','a')) {
+ avio_skip(pb, key_size);
+ }
+ c->meta_keys[i] = av_mallocz(key_size + 1);
+ if (!c->meta_keys[i])
+ return AVERROR(ENOMEM);
+ avio_read(pb, c->meta_keys[i], key_size);
+ }
+
+ return 0;
+}
+
static int mov_read_custom_2plus(MOVContext *c, AVIOContext *pb, int size)
{
int64_t end = avio_tell(pb) + size;
@@ -4071,6 +4137,14 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
atom.type == MKTAG('i','l','s','t')))
parse = mov_read_udta_string;
+ // Supports parsing the QuickTime Metadata Keys.
+ // https://developer.apple.com/library/mac/documentation/QuickTime/QTFF/Metadata/Metadata.html
+ if (!parse && c->found_hdlr_mdta &&
+ atom.type == MKTAG('m','e','t','a') &&
+ a.type == MKTAG('k','e','y','s')) {
+ parse = mov_read_keys;
+ }
+
if (!parse) { /* skip leaf atoms data */
avio_skip(pb, a.size);
} else {
@@ -4352,6 +4426,13 @@ static int mov_read_close(AVFormatContext *s)
mov->dv_fctx = NULL;
}
+ if (mov->meta_keys) {
+ for (i = 1; i < mov->meta_keys_count; i++) {
+ av_freep(&mov->meta_keys[i]);
+ }
+ av_freep(&mov->meta_keys);
+ }
+
av_freep(&mov->trex_data);
av_freep(&mov->bitrates);
--
2.6.0.rc2.230.g3dd15c0
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