1/*
2 * Targa (.tga) image encoder
3 * Copyright (c) 2007 Bobby Bingham
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#include <string.h>
23
24#include "libavutil/internal.h"
25#include "libavutil/intreadwrite.h"
26#include "libavutil/pixdesc.h"
27#include "avcodec.h"
28#include "internal.h"
29#include "rle.h"
30#include "targa.h"
31
32/**
33 * RLE compress the image, with maximum size of out_size
34 * @param outbuf Output buffer
35 * @param out_size Maximum output size
36 * @param pic Image to compress
37 * @param bpp Bytes per pixel
38 * @param w Image width
39 * @param h Image height
40 * @return Size of output in bytes, or -1 if larger than out_size
41 */
42static int targa_encode_rle(uint8_t *outbuf, int out_size, const AVFrame *pic,
43                            int bpp, int w, int h)
44{
45    int y,ret;
46    uint8_t *out;
47
48    out = outbuf;
49
50    for(y = 0; y < h; y ++) {
51        ret = ff_rle_encode(out, out_size, pic->data[0] + pic->linesize[0] * y, bpp, w, 0x7f, 0, -1, 0);
52        if(ret == -1){
53            return -1;
54        }
55        out+= ret;
56        out_size -= ret;
57    }
58
59    return out - outbuf;
60}
61
62static int targa_encode_normal(uint8_t *outbuf, const AVFrame *pic, int bpp, int w, int h)
63{
64    int i, n = bpp * w;
65    uint8_t *out = outbuf;
66    uint8_t *ptr = pic->data[0];
67
68    for(i=0; i < h; i++) {
69        memcpy(out, ptr, n);
70        out += n;
71        ptr += pic->linesize[0];
72    }
73
74    return out - outbuf;
75}
76
77static int targa_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
78                              const AVFrame *p, int *got_packet)
79{
80    int bpp, picsize, datasize = -1, ret, i;
81    uint8_t *out;
82
83    if(avctx->width > 0xffff || avctx->height > 0xffff) {
84        av_log(avctx, AV_LOG_ERROR, "image dimensions too large\n");
85        return AVERROR(EINVAL);
86    }
87    picsize = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
88    if ((ret = ff_alloc_packet2(avctx, pkt, picsize + 45)) < 0)
89        return ret;
90
91    /* zero out the header and only set applicable fields */
92    memset(pkt->data, 0, 12);
93    AV_WL16(pkt->data+12, avctx->width);
94    AV_WL16(pkt->data+14, avctx->height);
95    /* image descriptor byte: origin is always top-left, bits 0-3 specify alpha */
96    pkt->data[17] = 0x20 | (avctx->pix_fmt == AV_PIX_FMT_BGRA ? 8 : 0);
97
98    out = pkt->data + 18;  /* skip past the header we write */
99
100    avctx->bits_per_coded_sample = av_get_bits_per_pixel(av_pix_fmt_desc_get(avctx->pix_fmt));
101    switch(avctx->pix_fmt) {
102    case AV_PIX_FMT_PAL8: {
103        int pal_bpp = 24; /* Only write 32bit palette if there is transparency information */
104        for (i = 0; i < 256; i++)
105            if (AV_RN32(p->data[1] + 4 * i) >> 24 != 0xFF) {
106                pal_bpp = 32;
107                break;
108            }
109        pkt->data[1]  = 1;          /* palette present */
110        pkt->data[2]  = TGA_PAL;    /* uncompressed palettised image */
111        pkt->data[6]  = 1;          /* palette contains 256 entries */
112        pkt->data[7]  = pal_bpp;    /* palette contains pal_bpp bit entries */
113        pkt->data[16] = 8;          /* bpp */
114        for (i = 0; i < 256; i++)
115            if (pal_bpp == 32) {
116                AV_WL32(pkt->data + 18 + 4 * i, *(uint32_t *)(p->data[1] + i * 4));
117            } else {
118            AV_WL24(pkt->data + 18 + 3 * i, *(uint32_t *)(p->data[1] + i * 4));
119            }
120        out += 32 * pal_bpp;        /* skip past the palette we just output */
121        break;
122        }
123    case AV_PIX_FMT_GRAY8:
124        pkt->data[2]  = TGA_BW;     /* uncompressed grayscale image */
125        avctx->bits_per_coded_sample = 0x28;
126        pkt->data[16] = 8;          /* bpp */
127        break;
128    case AV_PIX_FMT_RGB555LE:
129        pkt->data[2]  = TGA_RGB;    /* uncompressed true-color image */
130        avctx->bits_per_coded_sample =
131        pkt->data[16] = 16;         /* bpp */
132        break;
133    case AV_PIX_FMT_BGR24:
134        pkt->data[2]  = TGA_RGB;    /* uncompressed true-color image */
135        pkt->data[16] = 24;         /* bpp */
136        break;
137    case AV_PIX_FMT_BGRA:
138        pkt->data[2]  = TGA_RGB;    /* uncompressed true-color image */
139        pkt->data[16] = 32;         /* bpp */
140        break;
141    default:
142        av_log(avctx, AV_LOG_ERROR, "Pixel format '%s' not supported.\n",
143               av_get_pix_fmt_name(avctx->pix_fmt));
144        return AVERROR(EINVAL);
145    }
146    bpp = pkt->data[16] >> 3;
147
148    /* try RLE compression */
149    if (avctx->coder_type != FF_CODER_TYPE_RAW)
150        datasize = targa_encode_rle(out, picsize, p, bpp, avctx->width, avctx->height);
151
152    /* if that worked well, mark the picture as RLE compressed */
153    if(datasize >= 0)
154        pkt->data[2] |= TGA_RLE;
155
156    /* if RLE didn't make it smaller, go back to no compression */
157    else datasize = targa_encode_normal(out, p, bpp, avctx->width, avctx->height);
158
159    out += datasize;
160
161    /* The standard recommends including this section, even if we don't use
162     * any of the features it affords. TODO: take advantage of the pixel
163     * aspect ratio and encoder ID fields available? */
164    memcpy(out, "\0\0\0\0\0\0\0\0TRUEVISION-XFILE.", 26);
165
166    pkt->size   = out + 26 - pkt->data;
167    pkt->flags |= AV_PKT_FLAG_KEY;
168    *got_packet = 1;
169
170    return 0;
171}
172
173static av_cold int targa_encode_init(AVCodecContext *avctx)
174{
175    avctx->coded_frame = av_frame_alloc();
176    if (!avctx->coded_frame)
177        return AVERROR(ENOMEM);
178
179    avctx->coded_frame->key_frame = 1;
180    avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
181
182    return 0;
183}
184
185static av_cold int targa_encode_close(AVCodecContext *avctx)
186{
187    av_frame_free(&avctx->coded_frame);
188    return 0;
189}
190
191AVCodec ff_targa_encoder = {
192    .name           = "targa",
193    .long_name      = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
194    .type           = AVMEDIA_TYPE_VIDEO,
195    .id             = AV_CODEC_ID_TARGA,
196    .init           = targa_encode_init,
197    .close          = targa_encode_close,
198    .encode2        = targa_encode_frame,
199    .pix_fmts       = (const enum AVPixelFormat[]){
200        AV_PIX_FMT_BGR24, AV_PIX_FMT_BGRA, AV_PIX_FMT_RGB555LE, AV_PIX_FMT_GRAY8, AV_PIX_FMT_PAL8,
201        AV_PIX_FMT_NONE
202    },
203};
204