Alias PIX image encoder and decoder

Changelog

@@ -5,6 +5,7 @@ version <next>:
 - libx265 encoder
 - shuffleplanes filter
 - replaygain data export
+- Alias PIX image encoder and decoder
 
 
 version 10:

doc/general.texi

@@ -424,6 +424,8 @@ following image formats are supported:
 @item Name @tab Encoding @tab Decoding @tab Comments
 @item .Y.U.V       @tab X @tab X
     @tab one raw file per component
+@item Alias PIX    @tab X @tab X
+    @tab Alias/Wavefront PIX image format
 @item animated GIF @tab X @tab X
     @tab Only uncompressed GIFs are generated.
 @item BMP          @tab X @tab X

libavcodec/Makefile

@@ -90,6 +90,8 @@ OBJS-$(CONFIG_AC3_FIXED_ENCODER)       += ac3enc_fixed.o ac3enc.o ac3tab.o ac3.o
 OBJS-$(CONFIG_AIC_DECODER)             += aic.o
 OBJS-$(CONFIG_ALAC_DECODER)            += alac.o alac_data.o
 OBJS-$(CONFIG_ALAC_ENCODER)            += alacenc.o alac_data.o
+OBJS-$(CONFIG_ALIAS_PIX_DECODER)       += aliaspixdec.o
+OBJS-$(CONFIG_ALIAS_PIX_ENCODER)       += aliaspixenc.o
 OBJS-$(CONFIG_ALS_DECODER)             += alsdec.o bgmc.o mpeg4audio.o
 OBJS-$(CONFIG_AMRNB_DECODER)           += amrnbdec.o celp_filters.o   \
                                           celp_math.o acelp_filters.o \

libavcodec/aliaspixdec.c

@@ -0,0 +1,128 @@
+/*
+ * Alias PIX image decoder
+ * Copyright (C) 2014 Vittorio Giovara <vittorio.giovara@gmail.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intreadwrite.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+
+#define ALIAS_HEADER_SIZE 10
+
+static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+                        AVPacket *avpkt)
+{
+    AVFrame *f = data;
+    GetByteContext gb;
+    int width, height, ret, bits_pixel, pixel;
+    uint8_t *out_buf;
+    uint8_t count;
+    int x, y;
+
+    bytestream2_init(&gb, avpkt->data, avpkt->size);
+
+    if (bytestream2_get_bytes_left(&gb) < ALIAS_HEADER_SIZE) {
+        av_log(avctx, AV_LOG_ERROR, "Header too small %d.\n", avpkt->size);
+        return AVERROR_INVALIDDATA;
+    }
+
+    width  = bytestream2_get_be16u(&gb);
+    height = bytestream2_get_be16u(&gb);
+    bytestream2_skipu(&gb, 4); // obsolete X, Y offset
+    bits_pixel = bytestream2_get_be16u(&gb);
+
+    if (bits_pixel == 24)
+        avctx->pix_fmt = AV_PIX_FMT_BGR24;
+    else if (bits_pixel == 8)
+        avctx->pix_fmt = AV_PIX_FMT_GRAY8;
+    else {
+        av_log(avctx, AV_LOG_ERROR, "Invalid pixel format.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    ret = ff_set_dimensions(avctx, width, height);
+    if (ret < 0)
+        return ret;
+
+    ret = ff_get_buffer(avctx, f, 0);
+    if (ret < 0)
+        return ret;
+
+    f->pict_type = AV_PICTURE_TYPE_I;
+    f->key_frame = 1;
+
+    x = 0;
+    y = 1;
+    out_buf = f->data[0];
+    while (bytestream2_get_bytes_left(&gb) > 0) {
+        int i;
+
+        /* set buffer at the right position at every new line */
+        if (x == avctx->width) {
+            x = 0;
+            out_buf = f->data[0] + f->linesize[0] * y++;
+            if (y > avctx->height) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Ended frame decoding with %d bytes left.\n",
+                       bytestream2_get_bytes_left(&gb));
+                return AVERROR_INVALIDDATA;
+            }
+        }
+
+        /* read packet and copy data */
+        count = bytestream2_get_byteu(&gb);
+        if (!count || x + count > avctx->width) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid run length %d.\n", count);
+            return AVERROR_INVALIDDATA;
+        }
+
+        if (avctx->pix_fmt == AV_PIX_FMT_BGR24) {
+            pixel = bytestream2_get_be24(&gb);
+            for (i = 0; i < count; i++) {
+                AV_WB24(out_buf, pixel);
+                out_buf += 3;
+            }
+        } else { // AV_PIX_FMT_GRAY8
+            pixel = bytestream2_get_byte(&gb);
+            for (i = 0; i < count; i++)
+                *out_buf++ = pixel;
+        }
+
+        x += i;
+    }
+
+    if (x != width || y != height) {
+        av_log(avctx, AV_LOG_ERROR, "Picture stopped at %d,%d.\n", x, y);
+        return AVERROR_INVALIDDATA;
+    }
+
+    *got_frame = 1;
+    return avpkt->size;
+}
+
+AVCodec ff_alias_pix_decoder = {
+    .name         = "alias_pix",
+    .long_name    = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
+    .type         = AVMEDIA_TYPE_VIDEO,
+    .id           = AV_CODEC_ID_ALIAS_PIX,
+    .decode       = decode_frame,
+    .capabilities = CODEC_CAP_DR1,
+};

libavcodec/aliaspixenc.c

@@ -0,0 +1,134 @@
+/*
+ * Alias PIX image encoder
+ * Copyright (C) 2014 Vittorio Giovara <vittorio.giovara@gmail.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intreadwrite.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+
+#define ALIAS_HEADER_SIZE 10
+
+static av_cold int encode_init(AVCodecContext *avctx)
+{
+    avctx->coded_frame = av_frame_alloc();
+    if (!avctx->coded_frame)
+        return AVERROR(ENOMEM);
+    return 0;
+}
+
+static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
+                        const AVFrame *frame, int *got_packet)
+{
+    int width, height, bits_pixel, i, j, length, ret;
+    uint8_t *in_buf, *buf;
+
+    avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
+    avctx->coded_frame->key_frame = 1;
+
+    width  = avctx->width;
+    height = avctx->height;
+
+    if (width > 65535 || height > 65535 ||
+        width * height >= INT_MAX / 4 - ALIAS_HEADER_SIZE) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n", width, height);
+        return AVERROR_INVALIDDATA;
+    }
+
+    switch (avctx->pix_fmt) {
+    case AV_PIX_FMT_GRAY8:
+        bits_pixel = 8;
+        break;
+    case AV_PIX_FMT_BGR24:
+        bits_pixel = 24;
+        break;
+    default:
+        return AVERROR(EINVAL);
+    }
+
+    length = ALIAS_HEADER_SIZE + 4 * width * height; // max possible
+    if ((ret = ff_alloc_packet(pkt, length)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Error getting output packet of size %d.\n", length);
+        return ret;
+    }
+
+    buf = pkt->data;
+
+    /* Encode header. */
+    bytestream_put_be16(&buf, width);
+    bytestream_put_be16(&buf, height);
+    bytestream_put_be32(&buf, 0); /* X, Y offset */
+    bytestream_put_be16(&buf, bits_pixel);
+
+    for (j = 0; j < height; j++) {
+        in_buf = frame->data[0] + frame->linesize[0] * j;
+        for (i = 0; i < width; ) {
+            int count = 0;
+            int pixel;
+
+            if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
+                pixel = *in_buf;
+                while (count < 255 && count + i < width && pixel == *in_buf) {
+                    count++;
+                    in_buf++;
+                }
+                bytestream_put_byte(&buf, count);
+                bytestream_put_byte(&buf, pixel);
+            } else { /* AV_PIX_FMT_BGR24 */
+                pixel = AV_RB24(in_buf);
+                while (count < 255 && count + i < width &&
+                       pixel == AV_RB24(in_buf)) {
+                    count++;
+                    in_buf += 3;
+                }
+                bytestream_put_byte(&buf, count);
+                bytestream_put_be24(&buf, pixel);
+            }
+            i += count;
+        }
+    }
+
+    /* Total length */
+    av_shrink_packet(pkt, buf - pkt->data);
+    pkt->flags |= AV_PKT_FLAG_KEY;
+    *got_packet = 1;
+
+    return 0;
+}
+
+static av_cold int encode_close(AVCodecContext *avctx)
+{
+    av_frame_free(&avctx->coded_frame);
+    return 0;
+}
+
+AVCodec ff_alias_pix_encoder = {
+    .name      = "alias_pix",
+    .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
+    .type      = AVMEDIA_TYPE_VIDEO,
+    .id        = AV_CODEC_ID_ALIAS_PIX,
+    .init      = encode_init,
+    .encode2   = encode_frame,
+    .close     = encode_close,
+    .pix_fmts  = (const enum AVPixelFormat[]) {
+        AV_PIX_FMT_BGR24, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
+    },
+};

libavcodec/allcodecs.c

@@ -98,6 +98,7 @@ void avcodec_register_all(void)
     REGISTER_ENCODER(A64MULTI5,         a64multi5);
     REGISTER_DECODER(AASC,              aasc);
     REGISTER_DECODER(AIC,               aic);
+    REGISTER_ENCDEC (ALIAS_PIX,         alias_pix);
     REGISTER_DECODER(AMV,               amv);
     REGISTER_DECODER(ANM,               anm);
     REGISTER_DECODER(ANSI,              ansi);

libavcodec/avcodec.h

@@ -284,6 +284,7 @@ enum AVCodecID {
     AV_CODEC_ID_HNM4_VIDEO,
     AV_CODEC_ID_HEVC,
     AV_CODEC_ID_FIC,
+    AV_CODEC_ID_ALIAS_PIX,
 
     /* various PCM "codecs" */
     AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs

libavcodec/codec_desc.c

@@ -1094,6 +1094,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
     },
 
     /* image codecs */
+    {
+        .id        = AV_CODEC_ID_ALIAS_PIX,
+        .type      = AVMEDIA_TYPE_VIDEO,
+        .name      = "alias_pix",
+        .long_name = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
+        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
+    },
     {
         .id        = AV_CODEC_ID_ANSI,
         .type      = AVMEDIA_TYPE_VIDEO,

libavcodec/version.h

@@ -29,7 +29,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 55
-#define LIBAVCODEC_VERSION_MINOR 36
+#define LIBAVCODEC_VERSION_MINOR 37
 #define LIBAVCODEC_VERSION_MICRO  0
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

libavformat/img2.c

@@ -43,6 +43,7 @@ static const IdStrMap img_tags[] = {
     { AV_CODEC_ID_PGMYUV,     "pgmyuv"   },
     { AV_CODEC_ID_PBM,        "pbm"      },
     { AV_CODEC_ID_PAM,        "pam"      },
+    { AV_CODEC_ID_ALIAS_PIX,  "pix"      },
     { AV_CODEC_ID_MPEG1VIDEO, "mpg1-img" },
     { AV_CODEC_ID_MPEG2VIDEO, "mpg2-img" },
     { AV_CODEC_ID_MPEG4,      "mpg4-img" },

libavformat/img2enc.c

@@ -148,7 +148,7 @@ AVOutputFormat ff_image2_muxer = {
     .long_name      = NULL_IF_CONFIG_SMALL("image2 sequence"),
     .extensions     = "bmp,dpx,jpeg,jpg,ljpg,pam,pbm,pcx,pgm,pgmyuv,png,"
                       "ppm,sgi,tga,tif,tiff,jp2,xwd,sun,ras,rs,im1,im8,im24,"
-                      "sunras,webp,xbm,j2c",
+                      "sunras,webp,xbm,j2c,pix",
     .priv_data_size = sizeof(VideoMuxData),
     .video_codec    = AV_CODEC_ID_MJPEG,
     .write_header   = write_header,