From 01a68c12a7cdf9031c19d1f00885a84d58e2c2a6 Mon Sep 17 00:00:00 2001 From: Mark Thompson Date: Fri, 1 Jan 2021 21:35:17 +0000 Subject: cbs: Implement common parts of cbs-based bitstream filters separately This allows removal of a lot of duplicated code between BSFs. --- libavcodec/Makefile | 2 +- libavcodec/cbs_bsf.c | 159 +++++++++++++++++++++++++++++++++++++++++++++++++++ libavcodec/cbs_bsf.h | 131 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 291 insertions(+), 1 deletion(-) create mode 100644 libavcodec/cbs_bsf.c create mode 100644 libavcodec/cbs_bsf.h (limited to 'libavcodec') diff --git a/libavcodec/Makefile b/libavcodec/Makefile index 1fcb94fa48..6c1e7a1c7a 100644 --- a/libavcodec/Makefile +++ b/libavcodec/Makefile @@ -69,7 +69,7 @@ OBJS-$(CONFIG_AUDIODSP) += audiodsp.o OBJS-$(CONFIG_BLOCKDSP) += blockdsp.o OBJS-$(CONFIG_BSWAPDSP) += bswapdsp.o OBJS-$(CONFIG_CABAC) += cabac.o -OBJS-$(CONFIG_CBS) += cbs.o +OBJS-$(CONFIG_CBS) += cbs.o cbs_bsf.o OBJS-$(CONFIG_CBS_AV1) += cbs_av1.o OBJS-$(CONFIG_CBS_H264) += cbs_h2645.o cbs_sei.o h2645_parse.o OBJS-$(CONFIG_CBS_H265) += cbs_h2645.o cbs_sei.o h2645_parse.o 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); +} diff --git a/libavcodec/cbs_bsf.h b/libavcodec/cbs_bsf.h new file mode 100644 index 0000000000..6be95abc3f --- /dev/null +++ b/libavcodec/cbs_bsf.h @@ -0,0 +1,131 @@ +/* + * 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 + */ + +#ifndef AVCODEC_CBS_BSF_H +#define AVCODEC_CBS_BSF_H + +#include "cbs.h" + + +typedef struct CBSBSFType { + enum AVCodecID codec_id; + + // Name of a frame fragment in this codec (e.g. "access unit", + // "temporal unit"). + const char *fragment_name; + + // Name of a unit for this BSF, for use in error messages (e.g. + // "NAL unit", "OBU"). + const char *unit_name; + + // Update the content of a fragment with whatever metadata changes + // are desired. The associated AVPacket is provided so that any side + // data associated with the fragment can be inspected or edited. If + // pkt is NULL, then an extradata header fragment is being updated. + int (*update_fragment)(AVBSFContext *bsf, AVPacket *pkt, + CodedBitstreamFragment *frag); +} CBSBSFType; + +// Common structure for all generic CBS BSF users. An instance of this +// structure must be the first member of the BSF private context (to be +// pointed to by AVBSFContext.priv_data). +typedef struct CBSBSFContext { + const AVClass *class; + const CBSBSFType *type; + + CodedBitstreamContext *input; + CodedBitstreamContext *output; + CodedBitstreamFragment fragment; +} CBSBSFContext; + +/** + * Initialise generic CBS BSF setup. + * + * Creates the input and output CBS instances, and applies the filter to + * the extradata on the input codecpar if any is present. + * + * Since it calls the update_fragment() function immediately to deal with + * extradata, this should be called after any codec-specific setup is done + * (probably at the end of the AVBitStreamFilter.init function). + */ +int ff_cbs_bsf_generic_init(AVBSFContext *bsf, const CBSBSFType *type); + +/** + * Close a generic CBS BSF instance. + * + * If no other deinitialisation is required then this function can be used + * directly as AVBitStreamFilter.close. + */ +void ff_cbs_bsf_generic_close(AVBSFContext *bsf); + +/** + * Filter operation for CBS BSF. + * + * Reads the input packet into a CBS fragment, calls update_fragment() on + * it, then writes the result to an output packet. If the input packet + * has AV_PKT_DATA_NEW_EXTRADATA side-data associated with it then it does + * the same thing to that new extradata to form the output side-data first. + * + * If the BSF does not do anything else then this function can be used + * directly as AVBitStreamFilter.filter. + */ +int ff_cbs_bsf_generic_filter(AVBSFContext *bsf, AVPacket *pkt); + + +// Options for element manipulation. +enum { + // Pass this element through unchanged. + BSF_ELEMENT_PASS, + // Insert this element, replacing any existing instances of it. + // Associated values may be provided explicitly (as addtional options) + // or implicitly (either as side data or deduced from other parts of + // the stream). + BSF_ELEMENT_INSERT, + // Remove this element if it appears in the stream. + BSF_ELEMENT_REMOVE, + // Extract this element to side data, so that further manipulation + // can happen elsewhere. + BSF_ELEMENT_EXTRACT, +}; + +#define BSF_ELEMENT_OPTIONS_PIR(name, help, field, opt_flags) \ + { name, help, OFFSET(field), AV_OPT_TYPE_INT, \ + { .i64 = BSF_ELEMENT_PASS }, \ + BSF_ELEMENT_PASS, BSF_ELEMENT_REMOVE, opt_flags, name }, \ + { "pass", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_PASS }, .flags = opt_flags, .unit = name }, \ + { "insert", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_INSERT }, .flags = opt_flags, .unit = name }, \ + { "remove", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_REMOVE }, .flags = opt_flags, .unit = name } + +#define BSF_ELEMENT_OPTIONS_PIRE(name, help, field, opt_flags) \ + { name, help, OFFSET(field), AV_OPT_TYPE_INT, \ + { .i64 = BSF_ELEMENT_PASS }, \ + BSF_ELEMENT_PASS, BSF_ELEMENT_EXTRACT, opt_flags, name }, \ + { "pass", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_PASS }, .flags = opt_flags, .unit = name }, \ + { "insert", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_INSERT }, .flags = opt_flags, .unit = name }, \ + { "remove", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_REMOVE }, .flags = opt_flags, .unit = name }, \ + { "extract", NULL, 0, AV_OPT_TYPE_CONST, \ + { .i64 = BSF_ELEMENT_EXTRACT }, .flags = opt_flags, .unit = name } \ + + +#endif /* AVCODEC_CBS_BSF_H */ -- cgit v1.2.3