1 /*
2 * HAPQA extract bitstream filter
3 * Copyright (c) 2017 Jokyo Images
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * HAPQA extract bitstream filter
25 * extract one of the two textures of the HAQA
26 */
27
28 #include "bsf.h"
29 #include "bsf_internal.h"
30 #include "bytestream.h"
31 #include "hap.h"
32
33 typedef struct HapqaExtractContext {
34 const AVClass *class;
35 int texture;/* index of the texture to keep (0 for rgb or 1 for alpha) */
36 } HapqaExtractContext;
37
check_texture(HapqaExtractContext * ctx,int section_type)38 static int check_texture(HapqaExtractContext *ctx, int section_type) {
39 if (((ctx->texture == 0)&&((section_type & 0x0F) == 0x0F)) || /* HapQ texture and rgb extract */
40 ((ctx->texture == 1)&&((section_type & 0x0F) == 0x01))) /* HapAlphaOnly texture and alpha extract */
41 {
42 return 1; /* the texture is the one to keep */
43 } else {
44 return 0;
45 }
46 }
47
hapqa_extract(AVBSFContext * bsf,AVPacket * pkt)48 static int hapqa_extract(AVBSFContext *bsf, AVPacket *pkt)
49 {
50 HapqaExtractContext *ctx = bsf->priv_data;
51 GetByteContext gbc;
52 int section_size;
53 enum HapSectionType section_type;
54 int start_section_size;
55 int target_packet_size = 0;
56 int ret = 0;
57
58 ret = ff_bsf_get_packet_ref(bsf, pkt);
59 if (ret < 0)
60 return ret;
61
62 bytestream2_init(&gbc, pkt->data, pkt->size);
63 ret = ff_hap_parse_section_header(&gbc, §ion_size, §ion_type);
64 if (ret != 0)
65 goto fail;
66
67 if ((section_type & 0x0F) != 0x0D) {
68 av_log(bsf, AV_LOG_ERROR, "Invalid section type for HAPQA %#04x.\n", section_type & 0x0F);
69 ret = AVERROR_INVALIDDATA;
70 goto fail;
71 }
72
73 start_section_size = 4;
74
75 bytestream2_seek(&gbc, start_section_size, SEEK_SET);/* go to start of the first texture */
76
77 ret = ff_hap_parse_section_header(&gbc, §ion_size, §ion_type);
78 if (ret != 0)
79 goto fail;
80
81 target_packet_size = section_size + 4;
82
83 if (check_texture(ctx, section_type) == 0) { /* the texture is not the one to keep */
84 start_section_size += 4 + section_size;
85 bytestream2_seek(&gbc, start_section_size, SEEK_SET);/* go to start of the second texture */
86 ret = ff_hap_parse_section_header(&gbc, §ion_size, §ion_type);
87 if (ret != 0)
88 goto fail;
89
90 target_packet_size = section_size + 4;
91
92 if (check_texture(ctx, section_type) == 0){ /* the second texture is not the one to keep */
93 av_log(bsf, AV_LOG_ERROR, "No valid texture found.\n");
94 ret = AVERROR_INVALIDDATA;
95 goto fail;
96 }
97 }
98
99 pkt->data += start_section_size;
100 pkt->size = target_packet_size;
101
102 fail:
103 if (ret < 0)
104 av_packet_unref(pkt);
105 return ret;
106 }
107
108 static const enum AVCodecID codec_ids[] = {
109 AV_CODEC_ID_HAP, AV_CODEC_ID_NONE,
110 };
111
112 #define OFFSET(x) offsetof(HapqaExtractContext, x)
113 #define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_BSF_PARAM)
114 static const AVOption options[] = {
115 { "texture", "texture to keep", OFFSET(texture), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, FLAGS, "texture" },
116 { "color", "keep HapQ texture", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, 0, 0, FLAGS, "texture" },
117 { "alpha", "keep HapAlphaOnly texture", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, 0, 0, FLAGS, "texture" },
118 { NULL },
119 };
120
121 static const AVClass hapqa_extract_class = {
122 .class_name = "hapqa_extract_bsf",
123 .item_name = av_default_item_name,
124 .option = options,
125 .version = LIBAVUTIL_VERSION_INT,
126 };
127
128 const AVBitStreamFilter ff_hapqa_extract_bsf = {
129 .name = "hapqa_extract",
130 .filter = hapqa_extract,
131 .priv_data_size = sizeof(HapqaExtractContext),
132 .priv_class = &hapqa_extract_class,
133 .codec_ids = codec_ids,
134 };
135