| 1 | /* |
| 2 | * Alias PIX image encoder |
| 3 | * Copyright (C) 2014 Vittorio Giovara <vittorio.giovara@gmail.com> |
| 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 "libavutil/intreadwrite.h" |
| 23 | |
| 24 | #include "avcodec.h" |
| 25 | #include "bytestream.h" |
| 26 | #include "internal.h" |
| 27 | |
| 28 | #define ALIAS_HEADER_SIZE 10 |
| 29 | |
| 30 | static av_cold int encode_init(AVCodecContext *avctx) |
| 31 | { |
| 32 | avctx->coded_frame = av_frame_alloc(); |
| 33 | if (!avctx->coded_frame) |
| 34 | return AVERROR(ENOMEM); |
| 35 | return 0; |
| 36 | } |
| 37 | |
| 38 | static int encode_frame(AVCodecContext *avctx, AVPacket *pkt, |
| 39 | const AVFrame *frame, int *got_packet) |
| 40 | { |
| 41 | int width, height, bits_pixel, i, j, length, ret; |
| 42 | uint8_t *in_buf, *buf; |
| 43 | |
| 44 | avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I; |
| 45 | avctx->coded_frame->key_frame = 1; |
| 46 | |
| 47 | width = avctx->width; |
| 48 | height = avctx->height; |
| 49 | |
| 50 | if (width > 65535 || height > 65535 || |
| 51 | width * height >= INT_MAX / 4 - ALIAS_HEADER_SIZE) { |
| 52 | av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n", width, height); |
| 53 | return AVERROR_INVALIDDATA; |
| 54 | } |
| 55 | |
| 56 | switch (avctx->pix_fmt) { |
| 57 | case AV_PIX_FMT_GRAY8: |
| 58 | bits_pixel = 8; |
| 59 | break; |
| 60 | case AV_PIX_FMT_BGR24: |
| 61 | bits_pixel = 24; |
| 62 | break; |
| 63 | default: |
| 64 | return AVERROR(EINVAL); |
| 65 | } |
| 66 | |
| 67 | length = ALIAS_HEADER_SIZE + 4 * width * height; // max possible |
| 68 | if ((ret = ff_alloc_packet(pkt, length)) < 0) { |
| 69 | av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", length); |
| 70 | return ret; |
| 71 | } |
| 72 | |
| 73 | buf = pkt->data; |
| 74 | |
| 75 | /* Encode header. */ |
| 76 | bytestream_put_be16(&buf, width); |
| 77 | bytestream_put_be16(&buf, height); |
| 78 | bytestream_put_be32(&buf, 0); /* X, Y offset */ |
| 79 | bytestream_put_be16(&buf, bits_pixel); |
| 80 | |
| 81 | for (j = 0; j < height; j++) { |
| 82 | in_buf = frame->data[0] + frame->linesize[0] * j; |
| 83 | for (i = 0; i < width; ) { |
| 84 | int count = 0; |
| 85 | int pixel; |
| 86 | |
| 87 | if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) { |
| 88 | pixel = *in_buf; |
| 89 | while (count < 255 && count + i < width && pixel == *in_buf) { |
| 90 | count++; |
| 91 | in_buf++; |
| 92 | } |
| 93 | bytestream_put_byte(&buf, count); |
| 94 | bytestream_put_byte(&buf, pixel); |
| 95 | } else { /* AV_PIX_FMT_BGR24 */ |
| 96 | pixel = AV_RB24(in_buf); |
| 97 | while (count < 255 && count + i < width && |
| 98 | pixel == AV_RB24(in_buf)) { |
| 99 | count++; |
| 100 | in_buf += 3; |
| 101 | } |
| 102 | bytestream_put_byte(&buf, count); |
| 103 | bytestream_put_be24(&buf, pixel); |
| 104 | } |
| 105 | i += count; |
| 106 | } |
| 107 | } |
| 108 | |
| 109 | /* Total length */ |
| 110 | av_shrink_packet(pkt, buf - pkt->data); |
| 111 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 112 | *got_packet = 1; |
| 113 | |
| 114 | return 0; |
| 115 | } |
| 116 | |
| 117 | static av_cold int encode_close(AVCodecContext *avctx) |
| 118 | { |
| 119 | av_frame_free(&avctx->coded_frame); |
| 120 | return 0; |
| 121 | } |
| 122 | |
| 123 | AVCodec ff_alias_pix_encoder = { |
| 124 | .name = "alias_pix", |
| 125 | .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"), |
| 126 | .type = AVMEDIA_TYPE_VIDEO, |
| 127 | .id = AV_CODEC_ID_ALIAS_PIX, |
| 128 | .init = encode_init, |
| 129 | .encode2 = encode_frame, |
| 130 | .close = encode_close, |
| 131 | .pix_fmts = (const enum AVPixelFormat[]) { |
| 132 | AV_PIX_FMT_BGR24, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE |
| 133 | }, |
| 134 | }; |