lavc: move bitstream filters into bsf/ subdir

1 files changed, 126 insertions, 0 deletions

diff --git a/libavcodec/bsf/h264_redundant_pps.c b/libavcodec/bsf/h264_redundant_pps.c
new file mode 100644
index 0000000000..df9a88a705
--- /dev/null
+++ b/libavcodec/bsf/h264_redundant_pps.c
@@ -0,0 +1,126 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <inttypes.h>
+
+#include "libavutil/log.h"
+
+#include "bsf.h"
+#include "bsf_internal.h"
+#include "cbs.h"
+#include "cbs_bsf.h"
+#include "cbs_h264.h"
+#include "codec_id.h"
+#include "h264.h"
+#include "packet.h"
+
+#define NEW_GLOBAL_PIC_INIT_QP 26
+
+typedef struct H264RedundantPPSContext {
+    CBSBSFContext common;
+} H264RedundantPPSContext;
+
+
+static int h264_redundant_pps_fixup_pps(H264RedundantPPSContext *ctx,
+                                        CodedBitstreamUnit *unit)
+{
+    H264RawPPS *pps;
+    int err;
+
+    // The changes we are about to perform affect the parsing process,
+    // so we must make sure that the PPS is writable, otherwise the
+    // parsing of future slices will be incorrect and even raise errors.
+    err = ff_cbs_make_unit_writable(ctx->common.input, unit);
+    if (err < 0)
+        return err;
+    pps = unit->content;
+
+    // Overwrite pic_init_qp with the global value.
+    pps->pic_init_qp_minus26 = NEW_GLOBAL_PIC_INIT_QP - 26;
+
+    // Some PPSs have this set, so it must be set in all of them.
+    // (Slices which do not use such a PPS on input will still have
+    // *_weight_l*flag as zero and therefore write equivalently.)
+    pps->weighted_pred_flag = 1;
+
+    return 0;
+}
+
+static int h264_redundant_pps_fixup_slice(H264RedundantPPSContext *ctx,
+                                          H264RawSliceHeader *slice)
+{
+    const CodedBitstreamH264Context *const in = ctx->common.input->priv_data;
+    const H264RawPPS *const pps = in->pps[slice->pic_parameter_set_id];
+
+    // We modified the PPS's qp value, now offset this by applying
+    // the negative offset to the slices.
+    slice->slice_qp_delta += pps->pic_init_qp_minus26
+                             - (NEW_GLOBAL_PIC_INIT_QP - 26);
+
+    return 0;
+}
+
+static int h264_redundant_pps_update_fragment(AVBSFContext *bsf,
+                                              AVPacket *pkt,
+                                              CodedBitstreamFragment *au)
+{
+    H264RedundantPPSContext *ctx = bsf->priv_data;
+    int err, i;
+
+    for (i = 0; i < au->nb_units; i++) {
+        CodedBitstreamUnit *nal = &au->units[i];
+
+        if (nal->type == H264_NAL_PPS) {
+            err = h264_redundant_pps_fixup_pps(ctx, nal);
+            if (err < 0)
+                return err;
+        }
+        if (nal->type == H264_NAL_SLICE ||
+            nal->type == H264_NAL_IDR_SLICE) {
+            H264RawSlice *slice = nal->content;
+            h264_redundant_pps_fixup_slice(ctx, &slice->header);
+        }
+    }
+
+    return 0;
+}
+
+static const CBSBSFType h264_redundant_pps_type = {
+    .codec_id        = AV_CODEC_ID_H264,
+    .fragment_name   = "access unit",
+    .unit_name       = "NAL unit",
+    .update_fragment = &h264_redundant_pps_update_fragment,
+};
+
+static int h264_redundant_pps_init(AVBSFContext *bsf)
+{
+    return ff_cbs_bsf_generic_init(bsf, &h264_redundant_pps_type);
+}
+
+static const enum AVCodecID h264_redundant_pps_codec_ids[] = {
+    AV_CODEC_ID_H264, AV_CODEC_ID_NONE,
+};
+
+const FFBitStreamFilter ff_h264_redundant_pps_bsf = {
+    .p.name         = "h264_redundant_pps",
+    .p.codec_ids    = h264_redundant_pps_codec_ids,
+    .priv_data_size = sizeof(H264RedundantPPSContext),
+    .init           = &h264_redundant_pps_init,
+    .close          = &ff_cbs_bsf_generic_close,
+    .filter         = &ff_cbs_bsf_generic_filter,
+};