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h264parse: parse SPS some more (e.g. for width/height)

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This commit is contained in:
Mark Nauwelaerts 2009-11-06 12:58:33 +01:00
parent 47041f610d
commit 291f45b383
1 changed files with 99 additions and 19 deletions
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118
gst/h264parse/gsth264parse.c
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@ -1,6 +1,9 @@
/* GStreamer h264 parser
* Copyright (C) 2005 Michal Benes <michal.benes@itonis.tv>
* (C) 2008 Wim Taymans <wim.taymans@gmail.com>
* (C) 2009 Mark Nauwelaerts <mnauw users sf net>
* (C) 2009 Nokia Corporation. All rights reserved.
* Contact: Stefan Kost <stefan.kost@nokia.com>
*
* gsth264parse.c:
*
@ -212,6 +215,20 @@ gst_nal_bs_read_ue (GstNalBs * bs)
return ((1 << i) - 1 + gst_nal_bs_read (bs, i));
}
/* read signed Exp-Golomb code */
static gint
gst_nal_bs_read_se (GstNalBs * bs)
{
gint i = 0;
i = gst_nal_bs_read_ue (bs);
/* (-1)^(i+1) Ceil (i / 2) */
i = (i + 1) / 2 * (i & 1 ? 1 : -1);
return i;
}
/* SEI type */
typedef enum
{
@ -276,6 +293,9 @@ struct _GstH264Sps
gboolean pic_struct_present_flag;
/* And more... */
/* derived values */
gint width, height;
};
/* PPS: pic parameter sets */
struct _GstH264Pps
@ -469,6 +489,11 @@ gst_nal_decode_sps (GstH264Parse * h, GstNalBs * bs)
guint8 profile_idc, level_idc;
guint8 sps_id;
GstH264Sps *sps = NULL;
guint subwc[] = { 1, 2, 2, 1 };
guint subhc[] = { 1, 2, 1, 1 };
guint chroma;
guint fc_top, fc_bottom, fc_left, fc_right;
gint width, height;
profile_idc = gst_nal_bs_read (bs, 8);
gst_nal_bs_read (bs, 1); /* constraint_set0_flag */
@ -489,15 +514,41 @@ gst_nal_decode_sps (GstH264Parse * h, GstNalBs * bs)
if (profile_idc == 100 || profile_idc == 110 || profile_idc == 122
|| profile_idc == 244 || profile_idc == 44 ||
profile_idc == 83 || profile_idc == 86) {
if (gst_nal_bs_read_ue (bs) == 3) { /* chroma_format_idc */
gst_nal_bs_read (bs, 1); /* separate_colour_plane_flag */
gint scp_flag = 0;
if ((chroma = gst_nal_bs_read_ue (bs)) == 3) { /* chroma_format_idc */
scp_flag = gst_nal_bs_read (bs, 1); /* separate_colour_plane_flag */
}
gst_nal_bs_read_ue (bs); /* bit_depth_luma_minus8 */
gst_nal_bs_read_ue (bs); /* bit_depth_chroma_minus8 */
gst_nal_bs_read (bs, 1); /* qpprime_y_zero_transform_bypass_flag */
if (gst_nal_bs_read (bs, 1)) { /* seq_scaling_matrix_present_flag */
/* TODO: unfinished */
gint i, j, m, d;
m = (chroma != 3) ? 8 : 12;
for (i = 0; i < m; i++) {
/* seq_scaling_list_present_flag[i] */
d = gst_nal_bs_read (bs, 1);
if (d) {
gint lastScale = 8, nextScale = 8, deltaScale;
j = (i < 6) ? 16 : 64;
for (; j > 0; j--) {
if (nextScale != 0) {
deltaScale = gst_nal_bs_read_se (bs);
nextScale = (lastScale + deltaScale + 256) % 256;
}
if (nextScale != 0)
lastScale = nextScale;
}
}
}
}
if (scp_flag)
chroma = 0;
} else {
/* inferred value */
chroma = 1;
}
sps->log2_max_frame_num_minus4 = gst_nal_bs_read_ue (bs); /* between 0 and 12 */
@ -511,35 +562,45 @@ gst_nal_decode_sps (GstH264Parse * h, GstNalBs * bs)
if (sps->pic_order_cnt_type == 0) {
sps->log2_max_pic_order_cnt_lsb_minus4 = gst_nal_bs_read_ue (bs);
} else if (sps->pic_order_cnt_type == 1) {
/* TODO: unfinished */
/*
delta_pic_order_always_zero_flag = gst_nal_bs_read (bs, 1);
offset_for_non_ref_pic = gst_nal_bs_read_se (bs);
offset_for_top_to_bottom_field = gst_nal_bs_read_se (bs);
gint d;
num_ref_frames_in_pic_order_cnt_cycle = gst_nal_bs_read_ue (bs);
for( i = 0; i < num_ref_frames_in_pic_order_cnt_cycle; i++ )
offset_for_ref_frame[i] = gst_nal_bs_read_se (bs);
*/
/* delta_pic_order_always_zero_flag */
gst_nal_bs_read (bs, 1);
/* offset_for_non_ref_pic */
gst_nal_bs_read_ue (bs);
/* offset_for_top_to_bottom_field */
gst_nal_bs_read_ue (bs);
/* num_ref_frames_in_pic_order_cnt_cycle */
d = gst_nal_bs_read_ue (bs);
for (; d > 0; d--) {
/* offset_for_ref_frame[i] */
gst_nal_bs_read_ue (bs);
}
}
gst_nal_bs_read_ue (bs); /* max_num_ref_frames */
gst_nal_bs_read (bs, 1); /* gaps_in_frame_num_value_allowed_flag */
gst_nal_bs_read_ue (bs); /* pic_width_in_mbs_minus1 */
gst_nal_bs_read_ue (bs); /* pic_height_in_map_units_minus1 */
width = gst_nal_bs_read_ue (bs); /* pic_width_in_mbs_minus1 */
height = gst_nal_bs_read_ue (bs); /* pic_height_in_map_units_minus1 */
sps->frame_mbs_only_flag = gst_nal_bs_read (bs, 1);
if (!sps->frame_mbs_only_flag) {
gst_nal_bs_read (bs, 1); /* mb_adaptive_frame_field_flag */
}
width++;
width *= 16;
height++;
height *= 16 * (2 - sps->frame_mbs_only_flag);
gst_nal_bs_read (bs, 1); /* direct_8x8_inference_flag */
if (gst_nal_bs_read (bs, 1)) { /* frame_cropping_flag */
gst_nal_bs_read_ue (bs); /* frame_crop_left_offset */
gst_nal_bs_read_ue (bs); /* frame_crop_right_offset */
gst_nal_bs_read_ue (bs); /* frame_crop_top_offset */
gst_nal_bs_read_ue (bs); /* frame_crop_bottom_offset */
}
fc_left = gst_nal_bs_read_ue (bs); /* frame_crop_left_offset */
fc_right = gst_nal_bs_read_ue (bs); /* frame_crop_right_offset */
fc_top = gst_nal_bs_read_ue (bs); /* frame_crop_top_offset */
fc_bottom = gst_nal_bs_read_ue (bs); /* frame_crop_bottom_offset */
} else
fc_left = fc_right = fc_top = fc_bottom = 0;
GST_DEBUG_OBJECT (h, "Decoding SPS: profile_idc = %d, "
"level_idc = %d, "
@ -550,6 +611,25 @@ gst_nal_decode_sps (GstH264Parse * h, GstNalBs * bs)
sps->level_idc,
sps_id, sps->pic_order_cnt_type, sps->frame_mbs_only_flag);
/* calculate width and height */
GST_DEBUG_OBJECT (h, "initial width=%d, height=%d", width, height);
GST_DEBUG_OBJECT (h, "crop (%d,%d)(%d,%d)",
fc_left, fc_top, fc_right, fc_bottom);
if (chroma > 3) {
GST_DEBUG_OBJECT (h, "chroma=%d in SPS is out of range", chroma);
return FALSE;
}
width -= (fc_left + fc_right) * subwc[chroma];
height -=
(fc_top + fc_bottom) * subhc[chroma] * (2 - sps->frame_mbs_only_flag);
if (width < 0 || height < 0) {
GST_DEBUG_OBJECT (h, "invalid width/height in SPS");
return FALSE;
}
GST_DEBUG_OBJECT (h, "final width=%u, height=%u", width, height);
sps->width = width;
sps->height = height;
sps->vui_parameters_present_flag = gst_nal_bs_read (bs, 1);
if (sps->vui_parameters_present_flag) {
gst_sps_decode_vui (h, bs);