cbs: Implement common parts of cbs-based bitstream filters separately

This allows removal of a lot of duplicated code between BSFs.

1 files changed, 159 insertions, 0 deletions

diff --git a/libavcodec/cbs_bsf.c b/libavcodec/cbs_bsf.c
new file mode 100644
index 0000000000..9b521cf111
--- /dev/null
+++ b/libavcodec/cbs_bsf.c
@@ -0,0 +1,159 @@
+/*
+ * 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 "bsf_internal.h"
+#include "cbs_bsf.h"
+
+static int cbs_bsf_update_side_data(AVBSFContext *bsf, AVPacket *pkt)
+{
+    CBSBSFContext           *ctx = bsf->priv_data;
+    CodedBitstreamFragment *frag = &ctx->fragment;
+    uint8_t *side_data;
+    int side_data_size;
+    int err;
+
+    side_data = av_packet_get_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
+                                        &side_data_size);
+    if (!side_data_size)
+        return 0;
+
+    err = ff_cbs_read(ctx->input, frag, side_data, side_data_size);
+    if (err < 0) {
+        av_log(bsf, AV_LOG_ERROR,
+               "Failed to read extradata from packet side data.\n");
+        return err;
+    }
+
+    err = ctx->type->update_fragment(bsf, NULL, frag);
+    if (err < 0)
+        return err;
+
+    err = ff_cbs_write_fragment_data(ctx->output, frag);
+    if (err < 0) {
+        av_log(bsf, AV_LOG_ERROR,
+               "Failed to write extradata into packet side data.\n");
+        return err;
+    }
+
+    side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
+                                        frag->data_size);
+    if (!side_data)
+        return AVERROR(ENOMEM);
+    memcpy(side_data, frag->data, frag->data_size);
+
+    ff_cbs_fragment_reset(frag);
+    return 0;
+}
+
+int ff_cbs_bsf_generic_filter(AVBSFContext *bsf, AVPacket *pkt)
+{
+    CBSBSFContext           *ctx = bsf->priv_data;
+    CodedBitstreamFragment *frag = &ctx->fragment;
+    int err;
+
+    err = ff_bsf_get_packet_ref(bsf, pkt);
+    if (err < 0)
+        return err;
+
+    err = cbs_bsf_update_side_data(bsf, pkt);
+    if (err < 0)
+        goto fail;
+
+    err = ff_cbs_read_packet(ctx->input, frag, pkt);
+    if (err < 0) {
+        av_log(bsf, AV_LOG_ERROR, "Failed to read %s from packet.\n",
+               ctx->type->fragment_name);
+        goto fail;
+    }
+
+    if (frag->nb_units == 0) {
+        av_log(bsf, AV_LOG_ERROR, "No %s found in packet.\n",
+               ctx->type->unit_name);
+        err = AVERROR_INVALIDDATA;
+        goto fail;
+    }
+
+    err = ctx->type->update_fragment(bsf, pkt, frag);
+    if (err < 0)
+        goto fail;
+
+    err = ff_cbs_write_packet(ctx->output, pkt, frag);
+    if (err < 0) {
+        av_log(bsf, AV_LOG_ERROR, "Failed to write %s into packet.\n",
+               ctx->type->fragment_name);
+        goto fail;
+    }
+
+    err = 0;
+fail:
+    ff_cbs_fragment_reset(frag);
+
+    if (err < 0)
+        av_packet_unref(pkt);
+
+    return err;
+}
+
+int ff_cbs_bsf_generic_init(AVBSFContext *bsf, const CBSBSFType *type)
+{
+    CBSBSFContext           *ctx = bsf->priv_data;
+    CodedBitstreamFragment *frag = &ctx->fragment;
+    int err;
+
+    ctx->type = type;
+
+    err = ff_cbs_init(&ctx->input, type->codec_id, bsf);
+    if (err < 0)
+        return err;
+
+    err = ff_cbs_init(&ctx->output, type->codec_id, bsf);
+    if (err < 0)
+        return err;
+
+    if (bsf->par_in->extradata) {
+        err = ff_cbs_read_extradata(ctx->input, frag, bsf->par_in);
+        if (err < 0) {
+            av_log(bsf, AV_LOG_ERROR, "Failed to read extradata.\n");
+            goto fail;
+        }
+
+        err = type->update_fragment(bsf, NULL, frag);
+        if (err < 0)
+            goto fail;
+
+        err = ff_cbs_write_extradata(ctx->output, bsf->par_out, frag);
+        if (err < 0) {
+            av_log(bsf, AV_LOG_ERROR, "Failed to write extradata.\n");
+            goto fail;
+        }
+    }
+
+    err = 0;
+fail:
+    ff_cbs_fragment_reset(frag);
+    return err;
+}
+
+void ff_cbs_bsf_generic_close(AVBSFContext *bsf)
+{
+    CBSBSFContext *ctx = bsf->priv_data;
+
+    ff_cbs_fragment_free(&ctx->fragment);
+    ff_cbs_close(&ctx->input);
+    ff_cbs_close(&ctx->output);
+}