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avformat/mxfdec: simply use the first essence element for non frame-wrapped partition essence offset

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Also add the canopus essence element to the list of the recognized essence
element keys.

Signed-off-by: Marton Balint <cus@passwd.hu>
This commit is contained in:
Marton Balint 2018-06-13 21:46:34 +02:00
parent 6345770eeb
commit f217be2cb8
1 changed files with 4 additions and 21 deletions
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25
libavformat/mxfdec.c
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@ -2785,14 +2785,6 @@ static int mxf_parse_handle_partition_or_eof(MXFContext *mxf)
return mxf->parsing_backward ? mxf_seek_to_previous_partition(mxf) : 1;
}
static int64_t round_to_kag(int64_t position, int kag_size)
{
/* TODO: account for run-in? the spec isn't clear whether KAG should account for it */
/* NOTE: kag_size may be any integer between 1 - 2^10 */
int64_t ret = (position / kag_size) * kag_size;
return ret == position ? ret : ret + kag_size;
}
static MXFWrappingScheme mxf_get_wrapping_by_body_sid(AVFormatContext *s, int body_sid)
{
for (int i = 0; i < s->nb_streams; i++) {
@ -2818,8 +2810,8 @@ static void mxf_compute_essence_containers(AVFormatContext *s)
if (!p->body_sid)
continue; /* BodySID == 0 -> no essence */
/* for non clip-wrapped essences we compute essence_offset
* for clip wrapped essences we point essence_offset after the KL (usually klv.offset + 20 or 25)
/* for clip wrapped essences we point essence_offset after the KL (usually klv.offset + 20 or 25)
* otherwise we point essence_offset at the key of the first essence KLV.
*/
wrapping = (mxf->op == OPAtom) ? ClipWrapped : mxf_get_wrapping_by_body_sid(s, p->body_sid);
@ -2828,17 +2820,7 @@ static void mxf_compute_essence_containers(AVFormatContext *s)
p->essence_offset = p->first_essence_klv.next_klv - p->first_essence_klv.length;
p->essence_length = p->first_essence_klv.length;
} else {
int64_t op1a_essence_offset =
p->this_partition +
round_to_kag(p->pack_length, p->kag_size) +
round_to_kag(p->header_byte_count, p->kag_size) +
round_to_kag(p->index_byte_count, p->kag_size);
/* NOTE: op1a_essence_offset may be less than to klv.offset (C0023S01.mxf) */
if (IS_KLV_KEY(p->first_essence_klv.key, mxf_system_item_key_cp) || IS_KLV_KEY(p->first_essence_klv.key, mxf_system_item_key_gc))
p->essence_offset = p->first_essence_klv.offset;
else
p->essence_offset = op1a_essence_offset;
p->essence_offset = p->first_essence_klv.offset;
/* essence container spans to the next partition */
if (x < mxf->partitions_count - 1)
@ -3057,6 +3039,7 @@ static int mxf_read_header(AVFormatContext *s)
av_log(s, AV_LOG_TRACE, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);
if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key) ||
IS_KLV_KEY(klv.key, mxf_essence_element_key) ||
IS_KLV_KEY(klv.key, mxf_canopus_essence_element_key) ||
IS_KLV_KEY(klv.key, mxf_avid_essence_element_key) ||
IS_KLV_KEY(klv.key, mxf_system_item_key_cp) ||
IS_KLV_KEY(klv.key, mxf_system_item_key_gc)) {