From 5f2f53a84d6bf3192463de83e55f3419823324b5 Mon Sep 17 00:00:00 2001
From: Martin Vignali <martin.vignali@gmail.com>
Date: Sun, 18 Feb 2018 19:29:33 +0100
Subject: [PATCH 2/3] avcodec/hapqa_extract_bsf : add new bsf filter

convert HapQA data to HAPQ or HAPAlphaOnly
by copying the corresponding texture
---
 libavcodec/Makefile            |   1 +
 libavcodec/bitstream_filters.c |   1 +
 libavcodec/hapqa_extract_bsf.c | 127 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 129 insertions(+)
 create mode 100644 libavcodec/hapqa_extract_bsf.c

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 3d4b738e0b..2eb68e28c9 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1029,6 +1029,7 @@ OBJS-$(CONFIG_DUMP_EXTRADATA_BSF)         += dump_extradata_bsf.o
 OBJS-$(CONFIG_DCA_CORE_BSF)               += dca_core_bsf.o
 OBJS-$(CONFIG_EXTRACT_EXTRADATA_BSF)      += extract_extradata_bsf.o    \
                                              h2645_parse.o
+OBJS-$(CONFIG_HAPQA_EXTRACT_BSF)          += hapqa_extract_bsf.o
 OBJS-$(CONFIG_H264_METADATA_BSF)          += h264_metadata_bsf.o
 OBJS-$(CONFIG_H264_MP4TOANNEXB_BSF)       += h264_mp4toannexb_bsf.o
 OBJS-$(CONFIG_H264_REDUNDANT_PPS_BSF)     += h264_redundant_pps_bsf.o
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index 338ef8251b..2537e91b40 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -29,6 +29,7 @@ extern const AVBitStreamFilter ff_chomp_bsf;
 extern const AVBitStreamFilter ff_dump_extradata_bsf;
 extern const AVBitStreamFilter ff_dca_core_bsf;
 extern const AVBitStreamFilter ff_extract_extradata_bsf;
+extern const AVBitStreamFilter ff_hapqa_extract_bsf;
 extern const AVBitStreamFilter ff_h264_metadata_bsf;
 extern const AVBitStreamFilter ff_h264_mp4toannexb_bsf;
 extern const AVBitStreamFilter ff_h264_redundant_pps_bsf;
diff --git a/libavcodec/hapqa_extract_bsf.c b/libavcodec/hapqa_extract_bsf.c
new file mode 100644
index 0000000000..ccf159e33d
--- /dev/null
+++ b/libavcodec/hapqa_extract_bsf.c
@@ -0,0 +1,127 @@
+/*
+ * 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 "avcodec.h"
+#include "bsf.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 hapqa_extract(AVBSFContext *bsf, AVPacket *out)
+{
+    HapqaExtractContext *ctx = bsf->priv_data;
+    GetByteContext gbc;
+    int section_size;
+    enum HapSectionType section_type;
+    int start_section_size;
+    int target_packet_size = 0;
+    AVPacket *in;
+    int ret = 0;
+    uint8_t *out_buf;
+
+    av_log(bsf, AV_LOG_DEBUG, "Texture to keep : %d.\n", ctx->texture);
+
+    ret = ff_bsf_get_packet(bsf, &in);
+    if (ret < 0)
+        return ret;
+
+    bytestream2_init(&gbc, in->data, in->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);
+        goto fail;
+    }
+
+    start_section_size = 4;
+
+    bytestream2_seek(&gbc, start_section_size, SEEK_SET);//On va au debut de la texture 0
+
+    ret = ff_hap_parse_section_header(&gbc, &section_size, &section_type);
+    if (ret != 0)
+        goto fail;
+
+    target_packet_size = section_size + 4;
+
+    if (ctx->texture == 1) {
+        start_section_size += 4 + section_size;
+        bytestream2_seek(&gbc, start_section_size, SEEK_SET);//On va au debut de la texture 1
+        ret = ff_hap_parse_section_header(&gbc, &section_size, &section_type);
+        if (ret != 0)
+            goto fail;
+
+        target_packet_size = section_size + 4;
+    }
+
+    ret = av_new_packet(out, target_packet_size);
+    if (ret < 0)
+        goto fail;
+
+    out_buf = out->data;
+    bytestream_put_buffer(&out_buf, in->data + start_section_size, target_packet_size);
+
+    ret = av_packet_copy_props(out, in);
+    if (ret < 0)
+        goto fail;
+
+fail:
+    if (ret < 0)
+        av_packet_unref(out);
+    av_packet_free(&in);
+    return ret;
+}
+
+static const enum AVCodecID codec_ids[] = {
+    AV_CODEC_ID_HAP, AV_CODEC_ID_NONE,
+};
+
+#define OFFSET(x) offsetof(HapqaExtractContext, x)
+static const AVOption options[] = {
+    { "texture", "texture to keep", OFFSET(texture), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, },
+    { NULL },
+};
+
+static const AVClass hapqa_extract_class = {
+    .class_name = "hapqa_extract_bsf",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_MAJOR,
+};
+
+const AVBitStreamFilter ff_hapqa_extract_bsf = {
+    .name       = "hapqa_extract",
+    .filter     = hapqa_extract,
+    .priv_data_size = sizeof(HapqaExtractContext),
+    .priv_class = &hapqa_extract_class,
+    .codec_ids  = codec_ids,
+};
-- 
2.14.3 (Apple Git-98)

