ffmpeg/libavcodec/hapqa_extract_bsf.c

135 lines
4.3 KiB
C

/*
* HAPQA extract bitstream filter
* Copyright (c) 2017 Jokyo Images
*
* 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
*/
/**
* @file
* HAPQA extract bitstream filter
* extract one of the two textures of the HAQA
*/
#include "bsf.h"
#include "bsf_internal.h"
#include "bytestream.h"
#include "hap.h"
typedef struct HapqaExtractContext {
const AVClass *class;
int texture;/* index of the texture to keep (0 for rgb or 1 for alpha) */
} HapqaExtractContext;
static int check_texture(HapqaExtractContext *ctx, int section_type) {
if (((ctx->texture == 0)&&((section_type & 0x0F) == 0x0F)) || /* HapQ texture and rgb extract */
((ctx->texture == 1)&&((section_type & 0x0F) == 0x01))) /* HapAlphaOnly texture and alpha extract */
{
return 1; /* the texture is the one to keep */
} else {
return 0;
}
}
static int hapqa_extract(AVBSFContext *bsf, AVPacket *pkt)
{
HapqaExtractContext *ctx = bsf->priv_data;
GetByteContext gbc;
int section_size;
enum HapSectionType section_type;
int start_section_size;
int target_packet_size = 0;
int ret = 0;
ret = ff_bsf_get_packet_ref(bsf, pkt);
if (ret < 0)
return ret;
bytestream2_init(&gbc, pkt->data, pkt->size);
ret = ff_hap_parse_section_header(&gbc, &section_size, &section_type);
if (ret != 0)
goto fail;
if ((section_type & 0x0F) != 0x0D) {
av_log(bsf, AV_LOG_ERROR, "Invalid section type for HAPQA %#04x.\n", section_type & 0x0F);
ret = AVERROR_INVALIDDATA;
goto fail;
}
start_section_size = 4;
bytestream2_seek(&gbc, start_section_size, SEEK_SET);/* go to start of the first texture */
ret = ff_hap_parse_section_header(&gbc, &section_size, &section_type);
if (ret != 0)
goto fail;
target_packet_size = section_size + 4;
if (check_texture(ctx, section_type) == 0) { /* the texture is not the one to keep */
start_section_size += 4 + section_size;
bytestream2_seek(&gbc, start_section_size, SEEK_SET);/* go to start of the second texture */
ret = ff_hap_parse_section_header(&gbc, &section_size, &section_type);
if (ret != 0)
goto fail;
target_packet_size = section_size + 4;
if (check_texture(ctx, section_type) == 0){ /* the second texture is not the one to keep */
av_log(bsf, AV_LOG_ERROR, "No valid texture found.\n");
ret = AVERROR_INVALIDDATA;
goto fail;
}
}
pkt->data += start_section_size;
pkt->size = target_packet_size;
fail:
if (ret < 0)
av_packet_unref(pkt);
return ret;
}
static const enum AVCodecID codec_ids[] = {
AV_CODEC_ID_HAP, AV_CODEC_ID_NONE,
};
#define OFFSET(x) offsetof(HapqaExtractContext, x)
#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_BSF_PARAM)
static const AVOption options[] = {
{ "texture", "texture to keep", OFFSET(texture), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, FLAGS, "texture" },
{ "color", "keep HapQ texture", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, 0, 0, FLAGS, "texture" },
{ "alpha", "keep HapAlphaOnly texture", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, 0, 0, FLAGS, "texture" },
{ NULL },
};
static const AVClass hapqa_extract_class = {
.class_name = "hapqa_extract_bsf",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFBitStreamFilter ff_hapqa_extract_bsf = {
.p.name = "hapqa_extract",
.p.codec_ids = codec_ids,
.p.priv_class = &hapqa_extract_class,
.priv_data_size = sizeof(HapqaExtractContext),
.filter = hapqa_extract,
};