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decoder: h264: fix detection of access unit boundaries.

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In order to have a stricter conforming implementation, we need to carefully
detect access unit boundaries. Additional operations could be necessary to
perform at those boundaries.
This commit is contained in:
Gwenole Beauchesne 2014-05-01 19:33:40 +02:00
parent a6215a0757
commit ae1d8267d9
1 changed files with 93 additions and 2 deletions
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95
gst-libs/gst/vaapi/gstvaapidecoder_h264.c
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@ -57,6 +57,27 @@ typedef struct _GstVaapiPictureH264 GstVaapiPictureH264;
/* --- H.264 Parser Info --- */
/* ------------------------------------------------------------------------- */
/*
* Extended decoder unit flags:
*
* @GST_VAAPI_DECODER_UNIT_AU_START: marks the start of an access unit.
* @GST_VAAPI_DECODER_UNIT_AU_END: marks the end of an access unit.
*/
enum {
/* This flag does not strictly follow the definitions (7.4.1.2.3)
for detecting the start of an access unit as we are only
interested in knowing if the current slice is the first one or
the last one in the current access unit */
GST_VAAPI_DECODER_UNIT_FLAG_AU_START = (
GST_VAAPI_DECODER_UNIT_FLAG_LAST << 0),
GST_VAAPI_DECODER_UNIT_FLAG_AU_END = (
GST_VAAPI_DECODER_UNIT_FLAG_LAST << 1),
GST_VAAPI_DECODER_UNIT_FLAGS_AU = (
GST_VAAPI_DECODER_UNIT_FLAG_AU_START |
GST_VAAPI_DECODER_UNIT_FLAG_AU_END),
};
#define GST_VAAPI_PARSER_INFO_H264(obj) \
((GstVaapiParserInfoH264 *)(obj))
@ -70,6 +91,7 @@ struct _GstVaapiParserInfoH264 {
GstH264SliceHdr slice_hdr;
} data;
guint state;
guint flags; // Same as decoder unit flags (persistent)
};
static void
@ -124,6 +146,10 @@ gst_vaapi_parser_info_h264_new(void)
* Extended picture flags:
*
* @GST_VAAPI_PICTURE_FLAG_IDR: flag that specifies an IDR picture
* @GST_VAAPI_PICTURE_FLAG_AU_START: flag that marks the start of an
* access unit (AU)
* @GST_VAAPI_PICTURE_FLAG_AU_END: flag that marks the end of an
* access unit (AU)
* @GST_VAAPI_PICTURE_FLAG_SHORT_TERM_REFERENCE: flag that specifies
* "used for short-term reference"
* @GST_VAAPI_PICTURE_FLAG_LONG_TERM_REFERENCE: flag that specifies
@ -134,6 +160,8 @@ gst_vaapi_parser_info_h264_new(void)
enum {
GST_VAAPI_PICTURE_FLAG_IDR = (GST_VAAPI_PICTURE_FLAG_LAST << 0),
GST_VAAPI_PICTURE_FLAG_REFERENCE2 = (GST_VAAPI_PICTURE_FLAG_LAST << 1),
GST_VAAPI_PICTURE_FLAG_AU_START = (GST_VAAPI_PICTURE_FLAG_LAST << 4),
GST_VAAPI_PICTURE_FLAG_AU_END = (GST_VAAPI_PICTURE_FLAG_LAST << 5),
GST_VAAPI_PICTURE_FLAG_SHORT_TERM_REFERENCE = (
GST_VAAPI_PICTURE_FLAG_REFERENCE),
@ -453,6 +481,25 @@ struct _GstVaapiDecoderH264Class {
static gboolean
exec_ref_pic_marking(GstVaapiDecoderH264 *decoder, GstVaapiPictureH264 *picture);
/* Determines the view order index (VOIdx) from the supplied view_id */
static gint
get_view_order_index(GstH264SPS *sps, guint16 view_id)
{
GstH264SPSExtMVC *mvc;
gint i;
if (!sps || sps->extension_type != GST_H264_NAL_EXTENSION_MVC)
return 0;
mvc = &sps->extension.mvc;
for (i = 0; i <= mvc->num_views_minus1; i++) {
if (mvc->view[i].view_id == view_id)
return i;
}
GST_ERROR("failed to find VOIdx from view_id (%d)", view_id);
return -1;
}
/* Get number of reference frames to use */
static guint
get_max_dec_frame_buffering(GstH264SPS *sps)
@ -2698,6 +2745,33 @@ is_new_picture(GstVaapiParserInfoH264 *pi, GstVaapiParserInfoH264 *prev_pi)
return FALSE;
}
/* Detection of a new access unit, assuming we are already in presence
of a new picture */
static gboolean
is_new_access_unit(GstVaapiParserInfoH264 *pi, GstVaapiParserInfoH264 *prev_pi)
{
GstH264SliceHdr * const slice_hdr = &pi->data.slice_hdr;
GstH264SliceHdr *prev_slice_hdr;
GstH264NalUnitExtensionMVC *mvc, *prev_mvc;
gint voc, prev_voc;
g_return_val_if_fail(is_new_picture(pi, prev_pi), FALSE);
if (!prev_pi)
return TRUE;
prev_slice_hdr = &prev_pi->data.slice_hdr;
mvc = &pi->nalu.extension.mvc;
prev_mvc = &prev_pi->nalu.extension.mvc;
if (mvc->view_id == prev_mvc->view_id)
return TRUE;
voc = get_view_order_index(slice_hdr->pps->sequence, mvc->view_id);
prev_voc = get_view_order_index(prev_slice_hdr->pps->sequence,
prev_mvc->view_id);
return voc < prev_voc;
}
static GstVaapiDecoderStatus
decode_picture(GstVaapiDecoderH264 *decoder, GstVaapiDecoderUnit *unit)
{
@ -2954,6 +3028,12 @@ decode_slice(GstVaapiDecoderH264 *decoder, GstVaapiDecoderUnit *unit)
return GST_VAAPI_DECODER_STATUS_ERROR_UNKNOWN;
}
/* Check wether this is the first/last slice in the current access unit */
if (pi->flags & GST_VAAPI_DECODER_UNIT_FLAG_AU_START)
GST_VAAPI_PICTURE_FLAG_SET(picture, GST_VAAPI_PICTURE_FLAG_AU_START);
if (pi->flags & GST_VAAPI_DECODER_UNIT_FLAG_AU_END)
GST_VAAPI_PICTURE_FLAG_SET(picture, GST_VAAPI_PICTURE_FLAG_AU_END);
slice = GST_VAAPI_SLICE_NEW(H264, decoder,
(map_info.data + unit->offset + pi->nalu.offset), pi->nalu.size);
gst_buffer_unmap(buffer, &map_info);
@ -3259,6 +3339,7 @@ gst_vaapi_decoder_h264_parse(GstVaapiDecoder *base_decoder,
flags = 0;
switch (pi->nalu.type) {
case GST_H264_NAL_AU_DELIMITER:
flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_START;
flags |= GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
/* fall-through */
case GST_H264_NAL_FILLER_DATA:
@ -3269,11 +3350,13 @@ gst_vaapi_decoder_h264_parse(GstVaapiDecoder *base_decoder,
/* fall-through */
case GST_H264_NAL_SEQ_END:
flags |= GST_VAAPI_DECODER_UNIT_FLAG_FRAME_END;
flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_END;
break;
case GST_H264_NAL_SPS:
case GST_H264_NAL_SUBSET_SPS:
case GST_H264_NAL_PPS:
case GST_H264_NAL_SEI:
flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_START;
flags |= GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
break;
case GST_H264_NAL_SLICE_EXT:
@ -3285,8 +3368,11 @@ gst_vaapi_decoder_h264_parse(GstVaapiDecoder *base_decoder,
case GST_H264_NAL_SLICE_IDR:
case GST_H264_NAL_SLICE:
flags |= GST_VAAPI_DECODER_UNIT_FLAG_SLICE;
if (is_new_picture(pi, priv->prev_slice_pi))
if (is_new_picture(pi, priv->prev_slice_pi)) {
flags |= GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
if (is_new_access_unit(pi, priv->prev_slice_pi))
flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_START;
}
gst_vaapi_parser_info_h264_replace(&priv->prev_slice_pi, pi);
break;
case GST_H264_NAL_SPS_EXT:
@ -3297,17 +3383,22 @@ gst_vaapi_decoder_h264_parse(GstVaapiDecoder *base_decoder,
case GST_H264_NAL_PREFIX_UNIT:
/* skip Prefix NAL units for now */
flags |= GST_VAAPI_DECODER_UNIT_FLAG_SKIP |
GST_VAAPI_DECODER_UNIT_FLAG_AU_START |
GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
break;
default:
if (pi->nalu.type >= 14 && pi->nalu.type <= 18)
flags |= GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_START |
GST_VAAPI_DECODER_UNIT_FLAG_FRAME_START;
break;
}
if ((flags & GST_VAAPI_DECODER_UNIT_FLAGS_AU) && priv->prev_slice_pi)
priv->prev_slice_pi->flags |= GST_VAAPI_DECODER_UNIT_FLAG_AU_END;
GST_VAAPI_DECODER_UNIT_FLAG_SET(unit, flags);
pi->nalu.data = NULL;
pi->state = priv->parser_state;
pi->flags = flags;
gst_vaapi_parser_info_h264_replace(&priv->prev_pi, pi);
return GST_VAAPI_DECODER_STATUS_SUCCESS;
}