Baptiste Coudurier <[email protected]> added the comment:
On 12/4/10 7:48 AM, Reimar Döffinger wrote:
>
> Reimar Döffinger <[email protected]> added the comment:
>
> On Sat, Dec 04, 2010 at 12:52:57PM +0000, Baptiste Coudurier wrote:
>>
>> Baptiste Coudurier <[email protected]> added the comment:
>>
>> On 12/4/10 4:45 AM, Deyan wrote:
>>>
>>> Deyan <[email protected]> added the comment:
>>>
>>>> 1. Your video starts out with digital black. Theora responds by
>>>> producing a single frame of black, and then zero-byte "dup frames"
>>>> indicating that nothing has changed. Some players are broken and don't
>>>> handle these frames correctly. Correctly working players, such as
>>>> Firefox, shouldn't have a problem, though.
>>>
>>> Considering the fact that this is visible on all players, including
>>> Firefox, I
>>> dont think this is a player issue.
>>> I mean it is unlikely that all players are broken :)
>>
>> I don't think either.
>> I see where the problem comes from, but unless we have a way to signal
>> these 0 bytes frames in some way (there may be one), this cannot be
>> fixed given the packing of packets in pages.
>> The only known timestamp is the one of the last packet of the page.
>> Let's say the encoder produced 0 bytes frame between the packets in the
>> page you don't know where they were if didn't signal them in some way,
>> and you cannot interpolate timestamps, that's why you see the "hang".
>
> So you need to end a page whenever a timestamp do not match the
> interpolated ones?
Yes, that should be a good strategy, patch attached, Deyan can you
please test it against firefox etc.. ?
________________________________________________
FFmpeg issue tracker <[email protected]>
<https://roundup.ffmpeg.org/issue2398>
________________________________________________
Index: libavformat/oggenc.c
===================================================================
--- libavformat/oggenc.c (revision 25874)
+++ libavformat/oggenc.c (working copy)
@@ -52,6 +52,7 @@
unsigned page_count; ///< number of page buffered
OGGPage page; ///< current page
unsigned serial_num; ///< serial number
+ int64_t last_granule; ///< last packet granule
} OGGStreamContext;
typedef struct OGGPageList {
@@ -110,13 +111,13 @@
return 0;
}
-static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, OGGPage
*page)
+static int64_t ogg_granule_to_timestamp(OGGStreamContext *oggstream, int64_t
granule)
{
if (oggstream->kfgshift)
- return (page->granule>>oggstream->kfgshift) +
- (page->granule & ((1<<oggstream->kfgshift)-1));
+ return (granule>>oggstream->kfgshift) +
+ (granule & ((1<<oggstream->kfgshift)-1));
else
- return page->granule;
+ return granule;
}
static int ogg_compare_granule(AVFormatContext *s, OGGPage *next, OGGPage
*page)
@@ -128,9 +129,9 @@
if (next->granule == -1 || page->granule == -1)
return 0;
- next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data, next),
+ next_granule = av_rescale_q(ogg_granule_to_timestamp(st2->priv_data,
next->granule),
st2->time_base, AV_TIME_BASE_Q);
- cur_granule = av_rescale_q(ogg_granule_to_timestamp(st->priv_data, page),
+ cur_granule = av_rescale_q(ogg_granule_to_timestamp(st->priv_data,
page->granule),
st ->time_base, AV_TIME_BASE_Q);
return next_granule > cur_granule;
}
@@ -174,8 +175,17 @@
OGGStreamContext *oggstream = st->priv_data;
int total_segments = size / 255 + 1;
uint8_t *p = data;
- int i, segments, len;
+ int i, segments, len, flush = 0;
+ // Handles VFR by flushing page because this frame needs to have a
timestamp
+ if (st->codec->codec_id == CODEC_ID_THEORA &&
+ ogg_granule_to_timestamp(oggstream, granule) >
+ ogg_granule_to_timestamp(oggstream, oggstream->last_granule) + 1) {
+ if (oggstream->page.granule != -1)
+ ogg_buffer_page(s, oggstream);
+ flush = 1;
+ }
+
for (i = 0; i < total_segments; ) {
OGGPage *page = &oggstream->page;
@@ -202,6 +212,10 @@
ogg_buffer_page(s, oggstream);
}
}
+
+ if (flush && oggstream->page.granule != -1)
+ ogg_buffer_page(s, oggstream);
+
return 0;
}
@@ -460,6 +474,8 @@
ogg_write_pages(s, 0);
+ oggstream->last_granule = granule;
+
return 0;
}
