org.jcodec.codecs.h264.io.read.SliceHeaderReader Maven / Gradle / Ivy
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Pure Java implementation of video/audio codecs and formats
package org.jcodec.codecs.h264.io.read;
import static org.jcodec.codecs.h264.io.model.RefPicReordering.InstrType.BACKWARD;
import static org.jcodec.codecs.h264.io.model.RefPicReordering.InstrType.FORWARD;
import static org.jcodec.codecs.h264.io.model.RefPicReordering.InstrType.LONG_TERM;
import java.io.IOException;
import java.util.ArrayList;
import org.jcodec.codecs.h264.StreamParams;
import org.jcodec.codecs.h264.io.model.ChromaFormat;
import org.jcodec.codecs.h264.io.model.NALUnit;
import org.jcodec.codecs.h264.io.model.NALUnitType;
import org.jcodec.codecs.h264.io.model.PictureParameterSet;
import org.jcodec.codecs.h264.io.model.PredictionWeightTable;
import org.jcodec.codecs.h264.io.model.RefPicMarking;
import org.jcodec.codecs.h264.io.model.RefPicMarkingIDR;
import org.jcodec.codecs.h264.io.model.RefPicReordering;
import org.jcodec.codecs.h264.io.model.SeqParameterSet;
import org.jcodec.codecs.h264.io.model.SliceHeader;
import org.jcodec.codecs.h264.io.model.SliceType;
import org.jcodec.codecs.h264.io.model.PredictionWeightTable.OffsetWeight;
import org.jcodec.codecs.h264.io.model.RefPicMarking.InstrType;
import org.jcodec.codecs.h264.io.model.RefPicMarking.Instruction;
import org.jcodec.codecs.h264.io.model.RefPicReordering.ReorderOp;
/**
* This class is part of JCodec ( www.jcodec.org ) This software is distributed
* under FreeBSD License
*
* Reads header of the coded slice
*
* @author Stanislav Vitvitskiy
*
*/
public class SliceHeaderReader {
private StreamParams streamParams;
public SliceHeaderReader(StreamParams demuxer) {
this.streamParams = demuxer;
}
public SliceHeader read(NALUnit nalUnit, CAVLCReader reader) throws IOException {
SliceHeader sh = new SliceHeader();
sh.first_mb_in_slice = reader.readUE("SH: first_mb_in_slice");
int sh_type = reader.readUE("SH: slice_type");
sh.slice_type = SliceType.fromValue(sh_type % 5);
sh.slice_type_restr = (sh_type / 5) > 0;
sh.pic_parameter_set_id = reader.readUE("SH: pic_parameter_set_id");
PictureParameterSet pps = streamParams.getPPS(sh.pic_parameter_set_id);
SeqParameterSet sps = streamParams.getSPS(pps.seq_parameter_set_id);
sh.pps = pps;
sh.sps = sps;
sh.frame_num = reader.readU(sps.log2_max_frame_num_minus4 + 4, "SH: frame_num");
if (!sps.frame_mbs_only_flag) {
sh.field_pic_flag = reader.readBool("SH: field_pic_flag");
if (sh.field_pic_flag) {
sh.bottom_field_flag = reader.readBool("SH: bottom_field_flag");
}
}
if (nalUnit.type == NALUnitType.IDR_SLICE) {
sh.idr_pic_id = reader.readUE("SH: idr_pic_id");
}
if (sps.pic_order_cnt_type == 0) {
sh.pic_order_cnt_lsb = reader.readU(sps.log2_max_pic_order_cnt_lsb_minus4 + 4, "SH: pic_order_cnt_lsb");
if (pps.pic_order_present_flag && !sps.field_pic_flag) {
sh.delta_pic_order_cnt_bottom = reader.readSE("SH: delta_pic_order_cnt_bottom");
}
}
sh.delta_pic_order_cnt = new int[2];
if (sps.pic_order_cnt_type == 1 && !sps.delta_pic_order_always_zero_flag) {
sh.delta_pic_order_cnt[0] = reader.readSE("SH: delta_pic_order_cnt[0]");
if (pps.pic_order_present_flag && !sps.field_pic_flag)
sh.delta_pic_order_cnt[1] = reader.readSE("SH: delta_pic_order_cnt[1]");
}
if (pps.redundant_pic_cnt_present_flag) {
sh.redundant_pic_cnt = reader.readUE("SH: redundant_pic_cnt");
}
if (sh.slice_type == SliceType.B) {
sh.direct_spatial_mv_pred_flag = reader.readBool("SH: direct_spatial_mv_pred_flag");
}
if (sh.slice_type == SliceType.P || sh.slice_type == SliceType.SP || sh.slice_type == SliceType.B) {
sh.num_ref_idx_active_override_flag = reader.readBool("SH: num_ref_idx_active_override_flag");
if (sh.num_ref_idx_active_override_flag) {
sh.num_ref_idx_l0_active_minus1 = reader.readUE("SH: num_ref_idx_l0_active_minus1");
if (sh.slice_type == SliceType.B) {
sh.num_ref_idx_l1_active_minus1 = reader.readUE("SH: num_ref_idx_l1_active_minus1");
}
}
}
readRefPicListReordering(sh, reader);
if ((pps.weighted_pred_flag && (sh.slice_type == SliceType.P || sh.slice_type == SliceType.SP))
|| (pps.weighted_bipred_idc == 1 && sh.slice_type == SliceType.B))
readPredWeightTable(sps, pps, sh, reader);
if (nalUnit.nal_ref_idc != 0)
readDecoderPicMarking(nalUnit, sh, reader);
if (pps.entropy_coding_mode_flag && sh.slice_type != SliceType.I && sh.slice_type != SliceType.SI) {
sh.cabac_init_idc = reader.readUE("SH: cabac_init_idc");
}
sh.slice_qp_delta = reader.readSE("SH: slice_qp_delta");
if (sh.slice_type == SliceType.SP || sh.slice_type == SliceType.SI) {
if (sh.slice_type == SliceType.SP) {
sh.sp_for_switch_flag = reader.readBool("SH: sp_for_switch_flag");
}
sh.slice_qs_delta = reader.readSE("SH: slice_qs_delta");
}
if (pps.deblocking_filter_control_present_flag) {
sh.disable_deblocking_filter_idc = reader.readUE("SH: disable_deblocking_filter_idc");
if (sh.disable_deblocking_filter_idc != 1) {
sh.slice_alpha_c0_offset_div2 = reader.readSE("SH: slice_alpha_c0_offset_div2");
sh.slice_beta_offset_div2 = reader.readSE("SH: slice_beta_offset_div2");
}
}
if (pps.num_slice_groups_minus1 > 0 && pps.slice_group_map_type >= 3 && pps.slice_group_map_type <= 5) {
int len = (sps.pic_height_in_map_units_minus1 + 1) * (sps.pic_width_in_mbs_minus1 + 1)
/ (pps.slice_group_change_rate_minus1 + 1);
if (((sps.pic_height_in_map_units_minus1 + 1) * (sps.pic_width_in_mbs_minus1 + 1))
% (pps.slice_group_change_rate_minus1 + 1) > 0)
len += 1;
len = CeilLog2(len + 1);
sh.slice_group_change_cycle = reader.readU(len, "SH: slice_group_change_cycle");
}
return sh;
}
private static int CeilLog2(int uiVal) {
int uiTmp = uiVal - 1;
int uiRet = 0;
while (uiTmp != 0) {
uiTmp >>= 1;
uiRet++;
}
return uiRet;
}
private static void readDecoderPicMarking(NALUnit nalUnit, SliceHeader sh, CAVLCReader reader) throws IOException {
if (nalUnit.type == NALUnitType.IDR_SLICE) {
boolean no_output_of_prior_pics_flag = reader.readBool("SH: no_output_of_prior_pics_flag");
boolean long_term_reference_flag = reader.readBool("SH: long_term_reference_flag");
sh.refPicMarkingIDR = new RefPicMarkingIDR(no_output_of_prior_pics_flag, long_term_reference_flag);
} else {
boolean adaptive_ref_pic_marking_mode_flag = reader.readBool("SH: adaptive_ref_pic_marking_mode_flag");
if (adaptive_ref_pic_marking_mode_flag) {
ArrayList mmops = new ArrayList();
int memory_management_control_operation;
do {
memory_management_control_operation = reader.readUE("SH: memory_management_control_operation");
Instruction instr = null;
switch (memory_management_control_operation) {
case 1:
instr = new RefPicMarking.Instruction(InstrType.REMOVE_SHORT,
reader.readUE("SH: difference_of_pic_nums_minus1") + 1, 0);
break;
case 2:
instr = new RefPicMarking.Instruction(InstrType.REMOVE_LONG,
reader.readUE("SH: long_term_pic_num"), 0);
break;
case 3:
instr = new RefPicMarking.Instruction(InstrType.CONVERT_INTO_LONG,
reader.readUE("SH: difference_of_pic_nums_minus1") + 1,
reader.readUE("SH: long_term_frame_idx"));
break;
case 4:
instr = new RefPicMarking.Instruction(InstrType.TRUNK_LONG,
reader.readUE("SH: max_long_term_frame_idx_plus1") - 1, 0);
break;
case 5:
instr = new RefPicMarking.Instruction(InstrType.CLEAR, 0, 0);
break;
case 6:
instr = new RefPicMarking.Instruction(InstrType.MARK_LONG,
reader.readUE("SH: long_term_frame_idx"), 0);
break;
}
if (instr != null)
mmops.add(instr);
} while (memory_management_control_operation != 0);
sh.refPicMarkingNonIDR = new RefPicMarking(mmops.toArray(new Instruction[] {}));
}
}
}
private static void readPredWeightTable(SeqParameterSet sps, PictureParameterSet pps, SliceHeader sh,
CAVLCReader reader) throws IOException {
sh.pred_weight_table = new PredictionWeightTable();
sh.pred_weight_table.luma_log2_weight_denom = reader.readUE("SH: luma_log2_weight_denom");
if (sps.chroma_format_idc != ChromaFormat.MONOCHROME) {
sh.pred_weight_table.chroma_log2_weight_denom = reader.readUE("SH: chroma_log2_weight_denom");
}
int numRefsL0 = sh.num_ref_idx_active_override_flag ? sh.num_ref_idx_l0_active_minus1 + 1
: pps.num_ref_idx_l0_active_minus1 + 1;
sh.pred_weight_table.luma_offset_weight_l0 = new OffsetWeight[numRefsL0];
sh.pred_weight_table.chroma_offset_weight_l0 = new OffsetWeight[numRefsL0][];
for (int i = 0; i < numRefsL0; i++) {
boolean luma_weight_l0_flag = reader.readBool("SH: luma_weight_l0_flag");
if (luma_weight_l0_flag) {
OffsetWeight ow = new OffsetWeight();
ow.weight = reader.readSE("SH: weight");
ow.offset = reader.readSE("SH: offset");
sh.pred_weight_table.luma_offset_weight_l0[i] = ow;
}
if (sps.chroma_format_idc != ChromaFormat.MONOCHROME) {
boolean chroma_weight_l0_flag = reader.readBool("SH: chroma_weight_l0_flag");
if (chroma_weight_l0_flag) {
sh.pred_weight_table.chroma_offset_weight_l0[i] = new OffsetWeight[2];
for (int j = 0; j < 2; j++) {
OffsetWeight ow = new OffsetWeight();
ow.weight = reader.readSE("SH: weight");
ow.offset = reader.readSE("SH: offset");
sh.pred_weight_table.chroma_offset_weight_l0[i][j] = ow;
}
}
}
}
if (sh.slice_type == SliceType.B) {
int numRefsL1 = sh.num_ref_idx_active_override_flag ? sh.num_ref_idx_l1_active_minus1 + 1
: pps.num_ref_idx_l1_active_minus1 + 1;
sh.pred_weight_table.luma_offset_weight_l1 = new OffsetWeight[numRefsL1];
sh.pred_weight_table.chroma_offset_weight_l1 = new OffsetWeight[numRefsL1][];
for (int i = 0; i < numRefsL1; i++) {
boolean luma_weight_l1_flag = reader.readBool("SH: luma_weight_l1_flag");
if (luma_weight_l1_flag) {
OffsetWeight ow = new OffsetWeight();
ow.weight = reader.readSE("SH: weight");
ow.offset = reader.readSE("SH: offset");
sh.pred_weight_table.luma_offset_weight_l1[i] = ow;
}
if (sps.chroma_format_idc != ChromaFormat.MONOCHROME) {
boolean chroma_weight_l1_flag = reader.readBool("SH: chroma_weight_l1_flag");
if (chroma_weight_l1_flag) {
sh.pred_weight_table.chroma_offset_weight_l1[i] = new OffsetWeight[2];
for (int j = 0; j < 2; j++) {
OffsetWeight ow = new OffsetWeight();
ow.weight = reader.readSE("SH: weight");
ow.offset = reader.readSE("SH: offset");
sh.pred_weight_table.chroma_offset_weight_l1[i][j] = ow;
}
}
}
}
}
}
private static void readRefPicListReordering(SliceHeader sh, CAVLCReader reader) throws IOException {
if (sh.slice_type != SliceType.I && sh.slice_type != SliceType.SI) {
boolean ref_pic_list_reordering_flag_l0 = reader.readBool("SH: ref_pic_list_reordering_flag_l0");
if (ref_pic_list_reordering_flag_l0) {
sh.refPicReorderingL0 = readReorderingEntries(reader);
}
}
if (sh.slice_type == SliceType.B) {
boolean ref_pic_list_reordering_flag_l1 = reader.readBool("SH: ref_pic_list_reordering_flag_l1");
if (ref_pic_list_reordering_flag_l1) {
sh.refPicReorderingL1 = readReorderingEntries(reader);
}
}
}
private static RefPicReordering readReorderingEntries(CAVLCReader reader) throws IOException {
ArrayList reordering = new ArrayList();
int reordering_of_pic_nums_idc;
do {
reordering_of_pic_nums_idc = reader.readUE("SH: reordering_of_pic_nums_idc");
switch (reordering_of_pic_nums_idc) {
case 0:
reordering.add(new ReorderOp(BACKWARD, reader.readUE("SH: abs_diff_pic_num_minus1") + 1));
break;
case 1:
reordering.add(new ReorderOp(FORWARD, reader.readUE("SH: abs_diff_pic_num_minus1") + 1));
break;
case 2:
reordering.add(new ReorderOp(LONG_TERM, reader.readUE("SH: long_term_pic_num")));
break;
}
} while (reordering_of_pic_nums_idc != 3);
return new RefPicReordering(reordering.toArray(new ReorderOp[] {}));
}
}
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