lavc: add a null bitstream filter

[ffmpeg] / libavcodec / c93.c

diff --git a/libavcodec/c93.c b/libavcodec/c93.c
index 589b123191888d2a952d30b7956556e8f5ab915f..18df9586d0a9afea40d37745e4a82e10b15b46e1 100644 (file)
--- a/libavcodec/c93.c
+++ b/libavcodec/c93.c
@@ -21,9 +21,10 @@
 
 #include "avcodec.h"
 #include "bytestream.h"
+#include "internal.h"
 
-typedef struct {
-    AVFrame pictures[2];
+typedef struct C93DecoderContext {
+    AVFrame *pictures[2];
     int currentpic;
 } C93DecoderContext;
 
@@ -45,20 +46,28 @@ typedef enum {
 #define C93_HAS_PALETTE 0x01
 #define C93_FIRST_FRAME 0x02
 
-static av_cold int decode_init(AVCodecContext *avctx)
+static av_cold int decode_end(AVCodecContext *avctx)
 {
-    avctx->pix_fmt = PIX_FMT_PAL8;
+    C93DecoderContext * const c93 = avctx->priv_data;
+
+    av_frame_free(&c93->pictures[0]);
+    av_frame_free(&c93->pictures[1]);
+
     return 0;
 }
 
-static av_cold int decode_end(AVCodecContext *avctx)
+static av_cold int decode_init(AVCodecContext *avctx)
 {
-    C93DecoderContext * const c93 = avctx->priv_data;
+    C93DecoderContext *s = avctx->priv_data;
+    avctx->pix_fmt = AV_PIX_FMT_PAL8;
+
+    s->pictures[0] = av_frame_alloc();
+    s->pictures[1] = av_frame_alloc();
+    if (!s->pictures[0] || !s->pictures[1]) {
+        decode_end(avctx);
+        return AVERROR(ENOMEM);
+    }
 
-    if (c93->pictures[0].data[0])
-        avctx->release_buffer(avctx, &c93->pictures[0]);
-    if (c93->pictures[1].data[0])
-        avctx->release_buffer(avctx, &c93->pictures[1]);
     return 0;
 }
 
@@ -79,7 +88,7 @@ static inline int copy_block(AVCodecContext *avctx, uint8_t *to,
     if (from_y + height > HEIGHT) {
         av_log(avctx, AV_LOG_ERROR, "invalid offset %d during C93 decoding\n",
                offset);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
 
     if (overflow > 0) {
@@ -113,26 +122,22 @@ static inline void draw_n_color(uint8_t *out, int stride, int width,
 }
 
 static int decode_frame(AVCodecContext *avctx, void *data,
-                            int *data_size, AVPacket *avpkt)
+                        int *got_frame, AVPacket *avpkt)
 {
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     C93DecoderContext * const c93 = avctx->priv_data;
-    AVFrame * const newpic = &c93->pictures[c93->currentpic];
-    AVFrame * const oldpic = &c93->pictures[c93->currentpic^1];
-    AVFrame *picture = data;
+    AVFrame * const newpic = c93->pictures[c93->currentpic];
+    AVFrame * const oldpic = c93->pictures[c93->currentpic^1];
     GetByteContext gb;
     uint8_t *out;
-    int stride, i, x, y, b, bt = 0;
+    int stride, ret, i, x, y, b, bt = 0;
 
     c93->currentpic ^= 1;
 
-    newpic->reference = 1;
-    newpic->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
-                         FF_BUFFER_HINTS_REUSABLE | FF_BUFFER_HINTS_READABLE;
-    if (avctx->reget_buffer(avctx, newpic)) {
+    if ((ret = ff_reget_buffer(avctx, newpic)) < 0) {
         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
-        return -1;
+        return ret;
     }
 
     stride = newpic->linesize[0];
@@ -162,8 +167,8 @@ static int decode_frame(AVCodecContext *avctx, void *data,
             switch (block_type) {
             case C93_8X8_FROM_PREV:
                 offset = bytestream2_get_le16(&gb);
-                if (copy_block(avctx, out, copy_from, offset, 8, stride))
-                    return -1;
+                if ((ret = copy_block(avctx, out, copy_from, offset, 8, stride)) < 0)
+                    return ret;
                 break;
 
             case C93_4X4_FROM_CURR:
@@ -172,9 +177,9 @@ static int decode_frame(AVCodecContext *avctx, void *data,
                 for (j = 0; j < 8; j += 4) {
                     for (i = 0; i < 8; i += 4) {
                         offset = bytestream2_get_le16(&gb);
-                        if (copy_block(avctx, &out[j*stride+i],
-                                           copy_from, offset, 4, stride))
-                            return -1;
+                        if ((ret = copy_block(avctx, &out[j*stride+i],
+                                              copy_from, offset, 4, stride)) < 0)
+                            return ret;
                     }
                 }
                 break;
@@ -221,7 +226,7 @@ static int decode_frame(AVCodecContext *avctx, void *data,
             default:
                 av_log(avctx, AV_LOG_ERROR, "unexpected type %x at %dx%d\n",
                        block_type, x, y);
-                return -1;
+                return AVERROR_INVALIDDATA;
             }
             bt >>= 4;
             out += 8;
@@ -233,25 +238,27 @@ static int decode_frame(AVCodecContext *avctx, void *data,
         for (i = 0; i < 256; i++) {
             palette[i] = bytestream2_get_be24(&gb);
         }
+        newpic->palette_has_changed = 1;
     } else {
         if (oldpic->data[1])
             memcpy(newpic->data[1], oldpic->data[1], 256 * 4);
     }
 
-    *picture = *newpic;
-    *data_size = sizeof(AVFrame);
+    if ((ret = av_frame_ref(data, newpic)) < 0)
+        return ret;
+    *got_frame = 1;
 
     return buf_size;
 }
 
 AVCodec ff_c93_decoder = {
     .name           = "c93",
+    .long_name      = NULL_IF_CONFIG_SMALL("Interplay C93"),
     .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = CODEC_ID_C93,
+    .id             = AV_CODEC_ID_C93,
     .priv_data_size = sizeof(C93DecoderContext),
     .init           = decode_init,
     .close          = decode_end,
     .decode         = decode_frame,
-    .capabilities   = CODEC_CAP_DR1,
-    .long_name      = NULL_IF_CONFIG_SMALL("Interplay C93"),
+    .capabilities   = AV_CODEC_CAP_DR1,
 };